Ray Optics And Optical Instruments Questions

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Ray Optics And Optical Instruments Questions

List of ray optics and optical instruments Questions

Question NoQuestionsClass
1An object is placed at a distance of 1.5 ( mathrm{m} ) from a screen and a convex lens is interposed between them. The
magnification produced is 4. The focal length of the lens is then
( A cdot 1 m )
B. 0.5 ( m )
c. ( 0.24 mathrm{m} )
D. ( 2 mathrm{m} )
12
2The intermediate image formed by the objective of a compound microscope is:
A. real, inverted and magnified
B. real, erect and magnifiedd
c. virtual, erect and magnified
D. virtual, inverted and magnified
12
3An object is kept at ( 15 mathrm{cm} ) from a convex mirror of focal length ( 25 mathrm{cm} . ) What is the magnification?
A ( cdot 4 / 9 )
B. 5/8
( c cdot 9 / 4 )
D. 8/5
12
4A ray of light is normally incident on one face of an equilateral glass prism. What will be the angle of incidence at the second face of the prism?
A ( cdot 0^{circ} )
B . ( 30^{circ} )
( c cdot 60^{circ} )
D. ( 90^{circ} )
12
5A ray deviates at ( 90^{circ} ) after suffering reflection from a mirror. The angle of incidence is:
A ( cdot 90^{circ} )
B. 30
( c cdot 60 )
( D cdot 45 )
12
6The focal length of a convex mirror is
its radius of curvature.
A. equal to
B. half of
c. two times
D. negative of
12
7The plano-convex lens of focal length 20 ( mathrm{cm} ) and ( 30 mathrm{cm} ) are placed together to form a double convex lens, the final
focal length will be :
( mathbf{A} cdot 12 mathrm{cm} )
B. ( 60 mathrm{cm} )
( mathbf{c} cdot 20 c m )
D. ( 30 mathrm{cm} )
12
8A convex lens forms a real image ( 4 mathrm{cm} )
long on a screen.When the lens is
shifted to a new position without disturbing the object or the screen, again real image is formed on the screen which is ( 16 mathrm{cm} ) long. The length of the object is :
A. ( 8 mathrm{cm} )
B. 10 ( mathrm{cm} )
c. ( 12 mathrm{cm} )
D. ( 6 mathrm{cm} )
12
9Explain total internal reflection using
diagram.
12
10How many types of prism are possible
( A )
B. 2
( c cdot 3 )
D. ( infty )
12
11An object is kept at a distance of ( 20 mathrm{cm} )
from a converging lens of focal length 10cm. What will be the magnification?
A ( cdot frac{1}{2} )
B.
c. 2
D.
12
12represents the passage of white light
through a prism?
( A )
3
( c )
( D )
12
13One cannot see through fog because
A. Fog absorbs light
B. Refractive index of fog is unity
C. Light suffers total internal reflection at the droplets in fog
D. Light is scattered by the droplets in fog
12
14For how long (approximate value) does the image remain on the retina?
A . ( 1 s )
B. ( 0.5 s )
c. ( 0.12 s )
D. ( 0.06 s )
12
15If the absolute refractive indices of glass and water are ( frac{3}{2} ) and ( frac{4}{3} ) respectively, what will be the velocity of light in water?
(If velocity of light in glass ( left.=2 times 10^{8}right) )
( mathbf{A} cdot 2.25 times 10^{8} m / s )
B . ( 3.25 times 10^{8} m / s )
C ( .2 .25 times 10^{7} mathrm{m} / mathrm{s} )
D. ( 2.15 times 10^{8} mathrm{m} / mathrm{s} )
12
16The angle between reflected ray and the
is called angle of reflection
A. normal
B. incident ray
c. reflecting surface
D. none of the above
12
17The magnification of plane mirror is always –
( mathbf{A} cdot1 )
( c .=1 )
D. zero
12
18A 27 mw laser beam has a cross-
sectional area of ( 10 mathrm{mm}^{2} ). The
magnitude of the maximum electric field in this electromagnetic wave is given by?[Given permittivity of space ( €_{0} )
( =9 times 10^{-12} mathrm{Sl} ) units, Speed of light ( c= )
( left.3 times 10^{8} m / sright] )
A. ( 1 mathrm{kV} / mathrm{m} )
B. 2 kv/m
c. ( 1.4 mathrm{kV} / mathrm{m} )
D. ( 0.7 mathrm{kV} / mathrm{m} )
12
19( mathbf{A} )
( 2.0 mathrm{cm} ) long object is placed perpendicular to the principal axis of a concave mirror. The distance of the
object from the mirror is ( 30 mathrm{cm}, ) and its image is formed ( 60 mathrm{cm} ) from the mirror
on the same side of the mirror as the
object. Find the height of the image formed:
A. 3 cm
в. 4 ст
( c .5 mathrm{cm} )
D. ( 8 mathrm{cm} )
12
20The pupil of the eye changes its size to adjust for
A. objects at different distances
B. different amount of light
c. objects of different sizes
D. different colours
12
21Which of the following principles has been followed to propagate light waves through an optical fibre?
A. Difraction
B. Interference
c. Total internal reflection
D. Scattering
12
22How may times total internal reflection
occurs in the drop for formation of primary and secondary rainbows?
12
23Explain the manner in which light travels with the help of an activity.12
24Two lens of focal length ( f_{1} ) and ( f_{2} ) are kept in contact coaxially. The resultant power of combination will be
A. ( frac{f_{1} f_{2}}{f_{1}-f_{2}} )
в. ( frac{f_{1}+f_{2}}{f_{1} f_{2}} )
c. ( f_{1}+f_{2} )
D. ( frac{f_{1}}{f_{2}}+frac{f_{2}}{f_{1}} )
12
25A monochromatic ray of light falls on a regular prism. What is the relation between angle of incidence and angle of emergence in the case of minimum deviation?12
26A concave mirror has a radius of
curvature ( 2 mathrm{m} . ) The light from a distance source is incident on the mirror. The
distance of the image of the source
from the mirror is:
( mathbf{A} cdot 0.5 m )
B. ( 1 m )
c. ( 1.5 m )
D. ( 2 m )
12
27The refracting angle of a prism is ( A ). The refractive index of the prism is ( cot frac{A}{2} ) Find angle of minimum deviation.
( mathbf{A} cdot 180^{circ}+2 A )
B ( cdot 180^{circ}-3 A )
D. ( 90^{circ}-A )
12
28Explain, why white light is dispersed when passing through a prism.12
29A ray of monochromatic light in
incident on one refracting face of a
prism of angle ( 75^{circ} . ) If passes through the prism and is incident on the other face at the critical angle. If refactive index of the material of the prism is ( sqrt{2} ) the angle of incidence on the first face
of the prism is
A ( cdot 30^{circ} )
B . ( 45^{circ} )
( c cdot 60^{circ} )
D. ( 0^{circ} )
12
30A ray of light from a liquid ( (mu=sqrt{3}) ) is
incident on a system of two right angled prism of refractive indices ( sqrt{3} a n d sqrt{2} )
as shown in the figure. The light suffers zero net deviation when it emerges into
air from surface CD. If the angle of incidence (in degrees) is ( 5 n . ) Find ( n ) ?
12
31White light is split into a spectrum by a prism and it is seen on a screen. If we
put another identical inverted prism behind it in contact. What will be seen
on the screen?
A. Violet will appear where red was
B. The spectrum will remain the same
c. There will be no spectrum, but only the original light with no deviation.
D. There will be no spectrum, but the original light will be laterally displaced
12
32The image of a candle flame formed by a lens is obtained on a screen placed on
the other side of the lens. If the image is
three times the size of the flame and
the distance between lens and image is ( 80 mathrm{cm}, ) at what distance should the candle be placed from the lens?
( mathbf{A} cdot 50 mathrm{cm} )
B. ( -36.67 mathrm{cm} )
( mathbf{c} .-26.67 mathrm{cm} )
D. ( 80 mathrm{cm} )
12
33Monochromatic light passes through a prism. Compares to that in air, inside the prism the light’s.
A. Speed and wavelength are different but frequency remains same
B. Speed and frequency are different but wavelength remains same
c. Frequency and wavelength are different but speed remains same
D. speed, wavelength and frequency are all different
12
34In the minimum deviation position of a prism, the refracted ray is always parallel to its base.
A. True
B. False
12
35In an experiment to determine the focal length ( (f) ) of a concave mirror by the
( u-v ) method, a student places the
object pin ( A ) on the principal axis at a distance ( x ) from the pole ( P . ) The student
looks at the pin and its inverted image from a distance keeping the eye in line with ( P A . ) When the student shifts the
eye towards left, the image appears to
the right of the object pin. Then:
A. ( x<f )
B. ( f<x2 f )
12
36Fig. 16.10 shows the word REST written in two ways in front of a mirror. Show how
the word would appear in the mirror.
The
12
37With regard to an astronomical telescope for refracting type, state how you will increase its:
(i) magnifying power.
(ii) resolving power
12
38Is the color of emergent beam ( X ) white
ight:
A. True
B. False
12
39To produce a minimum reflection of wavelengths near the middle of visible spectrum (550nm), how thick should a
coating of ( M g F_{2}(mu=1.38) ) be
vacuum-coated on a glass surface?
A ( cdot 10^{-7} )
B ( cdot 10^{-10} )
( mathbf{c} cdot 10^{-9} m )
D. ( 10^{-8} m )
12
40A light ray falls on the air glass
interface at an angle of ( 30^{circ} . ) What is the
angle of refraction for this rays? ( left(n_{a g}=frac{3}{2}right) )
12
41A ray of light is incident on a hollow
glass prism as shown. Then the ray will
undergo:
A. deviation and dispersion both
B. deviation but not dispersion
c. dispersion but no deviation
D. neither deviation nor dispersion
12
42A man who is ( 1.40 mathrm{m} ) tall stands in front
of a mirror and can just see himself from head to top. Assuming that his eyes are ( 0.14 mathrm{m} ) below the top of his head, the minimum height of the mirror is:
( A cdot 1.4 mathrm{m} )
B. ( 1.26 mathrm{m} )
c. ( 0.70 mathrm{m} )
D. 0.63 ( m )
12
43What is the reason behind the shinning of diamonds and how do you appreciate
it?
12
44When light is refracted from a surface, which of its following physical parameters does not change?
A. Velocity
B. Amplitude
c. Frequency
D. wavelength
12
45Two plane mirrors are placed as shown
in the figure and point object ‘O’ is
placed at the origin. Flnd how many
images will be formed
12
46The type of lens used as a simple microscope.
A. Binocular lens
B. Plano concave lens
c. concave convex lens
D. Convex lens
12
47Two identical equiconcex lenses made of glass of refractive index ( 1.5, ) placd in contact has power P. When a liquid of refractive index ( mu ) is filled in the gap between the lenses, the power becomes ( boldsymbol{P} )
( overline{mathbf{3}} )
( i f mu=frac{x}{3} . ) Find the value of ( x )
12
48A planet is observed by an astronomical reflecting telescope having an objective of focal length ( 16 m ) and an eye-piece of
focal length 2cm. Then:
This question has multiple correct options
A. the distance between the objective and the eye – piece is ( 16.02 m )
B. the angular magnification of the planet is 800
c. the image of planet is erect
D. the objective is larger than eye – piece
12
49A rod of length ( 10 mathrm{cm} ) lies along the principal axis of concave mirror of focal
length ( 10 c m ) in such a way that its end
closer to the pole is ( 20 mathrm{cm} ) away from the mirror. The length of the image is-
( mathbf{A} cdot 15 mathrm{cm} )
B. ( 2.5 mathrm{cm} )
( c .5 mathrm{cm} )
D. ( 10 mathrm{cm} )
12
50A point object is placed on the principal axis of the convex lens of focal length
( 20 mathrm{cm} ) at a distance ( 40 mathrm{cm} ) to the left on
it. The diameter of the lens is ( 10 mathrm{cm} ). If
the eye is placed 60cm to the right of the lens at a distance h below the
principal axis, then max value of ‘h’ to
see the image is
A . ( 1.5 mathrm{cm} )
B. 2.5 ( mathrm{cm} )
c. ( 3 mathrm{cm} )
D. ( 5 mathrm{cm} )
12
51Figures shows a convex lens cut
symmetrically into two equal halves and separated laterally by a distance h.
A point object placed at a distance 30 ( mathrm{cm}, ) from the lens halves, forms two real
images separated by a distance d. A plot of d versus h is shown in figure. The focal length of the lens is
A. 35 cm
B. ( 40 mathrm{cm} )
( c .45 mathrm{cm} )
D. ( 60 mathrm{cm} )
12
52A glass prism of refractive index 1.5 is
placed in water of refractive index 1.33 The minimum value of the angle of the prism so that it will not be possible to
have any emergent ray is :
A ( .150^{circ} )
B . ( 125^{circ} )
( c cdot 165 )
D. ( 180^{circ} )
12
53Which one is as incorrect match?
A. Myopia – Biconvex lens
B. Olfactory – Smell
C. Algerireceptor – Pain
D. Organ of corti cells – Sensory and supporting
12
54Find the focal length of a lens of power
(-2.0)D. What type of lens is this?
12
55State what is meant by refraction of light. State Snell’s law for refraction of
light and also express it mathematically. The refractive index of air with respect to glass is ( 2 / 3 ) and the refractive index
of water with respect to air is ( 4 / 3 . ) If the
speed of light in glass is ( 2 times 10^{8} mathrm{m} / mathrm{s} )
find the speed of light in (a) air, (b)
water
12
56Explain the phenomenon of total internal reflection of light with an
example. Draw necessary ray of diagram.
12
57Rays parallel to the principle axis are refracted by the lens through the point:
A .
B. 2F
( c cdot F )
D. None
12
58A biconvex lens is made of material of
refractive index 1.5 each of radius of
curvature of lens surface is ( 20 mathrm{cm} ). The
focal length of lens is:
A. ( 20 mathrm{cm} )
B. 10 ( mathrm{cm} )
( c cdot 25 mathrm{cm} )
D. 30 cm
12
59A luminous object is placed at a distance of ( 30 mathrm{cm} ) from a convex lens of
focal length ( 20 mathrm{cm} . ) On the other side of the lens, at what distance from the lens
must a convex mirror of radius of
curvature ( 10 mathrm{cm} ) be placed in order to have an upright image of the object coincident with it?
( A . ) 30 ( mathrm{cm} )
B. 40 cm
( c .50 mathrm{cm} )
D. ( 12 mathrm{cm} )
12
60Assertion
When white light fall on the compact disc, multicolours are seen after
reflection.
Reason
CD disc behaves like a prism.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion,
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
61A ray of light is incident on a plane
mirror at an angle of ( 30^{circ} . ) At what angle
with the horizontal must a plane mirror be placed so that the reflected ray becomes vertically upwards?
( A cdot 40^{circ} )
B. 20 ( ^{circ} )
( c cdot 30 )
D. ( 60^{circ} )
12
62Which one of the mirror below (in the
absence of the other mirrors) would
cause light from a distant source on the left side of the paper to be focussed to a
point that is closest to the mirror?
( A )
B. B
( c cdot c )
( D )
12
63A ray of light is incident normally on a plane glass slab. What will be the angle of refraction?
A ( cdot 90^{circ} )
B. ( 180^{circ} )
( c cdot 60^{circ} )
D. ( 0^{circ} )
12
64The laws of reflection hold good for:
A. plane mirror only
B. concave mirror only
C. convex mirror only
D. all mirrors irrespective of their shape
12
65Comparing real and virtual images, we
may say that
A. real images can not be obtained on a screen and virtual images can be
B. virtual images can not be obtained on a screen and real images can be
C. both real and virtual images can be obtained on a screen
D. neither real nor virtual images can be obtained on a screen
12
6614. A fish looking up through water sees the outside world
contained in a circular horizon. If the refractive index of
water is 4/3 and the fish is 12 cm below the surface, the
radius of this circle (in cm) is
(a) 475
(b) 36V5
(c) 3677
(AIEEE 2005)
12
67White light is incident normally on a glass slab. Inside the glass slab,
A. Red light travels faster than other colours
B. Violet light travels faster than other colours
c. Yellow light travels faster than other colours
D. All colours travel with the same speed
12
68An object 0 is placed in front of a mirror. Which is possible position of the image?
( A )
B. B
( c cdot c )
D.
12
69Scattering of light is defined as:
A. Splitting of light into its component colours
B. Deflection of light in different directions when light is incident on extremely small particles
c. Bending of light on change of medium
D. reversal of light direction from a shiny surface
12
70A person cannot see fundamental colours (red, blue, green). This defect is called:
A. myopia
B. presbyopia
c. colour blindness
D. astigmatism
12
71Large astronomical telescopes always use as objective
A. Iens
B. mirror
c. combinations of lenses
D. none of the above
12
72A small bulb is placed at the bottom of a tank containing water to a depth of 1 ( m ). Find the critical angle for water air
interface and also calculate the
diameter of the circular bright patch of light formed on the surface of water
[Refractive index of water ( =mathbf{1 . 3 3}] )
12
73Which of the following is/are the factors on which angle of deviation depend?
A. Refractive index of the prism
B. Angle of the prism
c. Angle of refraction
D. Both A and B
12
74No matter how far you stand from a mirror, your image always appears erect. Then the mirror among the following is likely to be:
A. a plane mirror
B. a concave mirror
c. any type of mirror
D. none of the above
12
75A beam of light converges at a point ( mathrm{P} ) Now a lens is placed in the path of the convergent beam ( 12 mathrm{cm} ) from P. At what
point does the beam converge if the lens
is
(a) a convex lens of focal length 20 ( mathrm{cm}, ) and (b) a concave lens of focal
length ( 16 mathrm{cm} ? )
12
76A light ray traveling from one medium
into another:
A. always bends towards the normal
B. always bends away from the normal
C. bends towards or away from the normal depending on the densities of the two media
D. never suffers a refraction
12
77Which colour of light deviates the maximum in the dispersion of white light by the prism?
A . Violet
B. Blue
c. Green
D. Red
12
78State the approximate value of the critical angle for (a) glass-air surface,
(b) water-air surface (Given ( mu_{text {glass}}= )
( left.mathbf{1 . 5}, boldsymbol{mu}_{boldsymbol{w} boldsymbol{a} boldsymbol{t} e r}=mathbf{1 . 3 3}right) )
A ( cdot ) (a) ( 49^{circ},(b) 49^{circ} )
B . (a) ( 42^{circ},(b) 42^{circ} )
( mathbf{c} cdot(mathbf{a}) 42^{o},(mathbf{b}) 49^{circ} )
D ( cdot ) (a) ( 49^{circ},(b) 42^{circ} )
12
79State the laws of reflection of light.12
80The ( x-y ) plane is the boundary
between two transparent media. Medium-1 with ( z>0 ) has refractive
index ( sqrt{2} ) and medium- 2 with ( z<0 ) has a refractive index ( sqrt{3} . ) A ray of light in medium-1 given by the vector ( overrightarrow{boldsymbol{A}}= ) ( 6 sqrt{3} hat{i}+8 sqrt{3} hat{j}-10 hat{k} ) is incident on the
plane of separation. Find the unit vector
in the direction of refracted ray in medium-2.
( mathbf{A} cdot 45^{circ} )
B. ( 60^{circ} )
( mathbf{c} cdot 75^{circ} )
D. 30 ( ^{circ} )
12
81A cubical room is formed with 6 plane
mirror. An insect moves along diagonal of the floor with uniform speed. The velocity of its image in two adjacent walls are ( 20 sqrt{2} mathrm{cm} / mathrm{s} ). Then the velocity of image formed by the roof is
( mathbf{A} cdot 20 mathrm{cm} / mathrm{sec} )
B. ( 40 mathrm{cm} / mathrm{sec} )
( mathrm{c} cdot 9 mathrm{cm} / mathrm{sec} )
D. ( 45 mathrm{cm} / mathrm{sec} )
12
82If ( C= ) the velocity of light, which of the following is correct?
( mathbf{A} cdot mu_{0} varepsilon_{0}=c )
В. ( mu_{0} varepsilon_{0}=c^{2} )
( mathbf{c} )
D. ( _{mu_{0} varepsilon_{0}}=frac{1}{c^{2}} )
12
83A uniform, horizontal beam of light is incident upon a prism as shown in the fig. The prism is in the shape of a
quarter cylinder of radius ( R=5 c m, ) and has a refractive index ( frac{2}{sqrt{3}} . ) A patch on the table for a distance ( x ) from the
cylinder is unilluminated. The value of ( x )
is
A . ( 2.5 mathrm{cm} )
в. 5 ст
( c cdot 5 sqrt{3} mathrm{cm} )
D. ( 10 mathrm{cm} )
12
84A convex lens is made of 3 layers of
glass of 3 different materials as in the figure. A point object is placed on its
axis. The number of images of the
object are
( A )
B.
( c .3 )
( D )
12
85In the Newton’s rings set up, when a drop of water is introduced between the
glass plate and planoconvex lens the observed ring system
A. Contracts
B. Expands
c. Remains the same
D. Expands and then contracts
12
86The clear sky appears blue because:
A. blue light gets absorbed in the atmosphere.
B. ultraviolet radiations are absorbed in the atmosphere.
C. violet and blue lights get scattered more than lights of all other colours by the atmosphere.
D. light of all other colours is scattered more than the violet and blue colour lights by the atmosphere.
12
87When the angle of reflection is ( 40^{circ}, ) then
the angle between normal and the
mirror will be
A .40
B. ( 90^{circ} )
( c cdot 45 )
D. ( 60^{circ} )
12
88A prism ( (mu=1.5) ) has the refracting
angle of ( 60^{circ} . ) The deviation of a monochromatic ray incident normally on its one surface will be ( left(sin 48^{circ} 36^{prime}=right. ) ( mathbf{0 . 7 5}) )
( mathbf{A} cdot 36^{circ} 72 )
B . ( 20^{circ} 30^{prime} )
( c cdot 18^{circ} )
D. ( 22^{circ} 1^{prime} )
12
89Assertion
The images formed by total internal reflections are much brighter than those formed by mirrors or lenses
Reason

There is no loss of intensity in total
internal reflection.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect

12
90Explain how you can take care of your
eyes.
12
91Write any two differences between regular and irregular (diffused) reflection12
92Fill in the blanks:
Magnification of convex mirror is in
range and of concave
mirror is in range
A ( (0,1),(-infty, 0) cup(1, infty) )
(1)
B . ( (-1,0),(-infty, infty) )
c. ( (-infty, infty),(1, infty) )
D ( cdot(-infty, infty),(-1,-infty) )
12
93Q Type your question
a convex lens.
Arrange the steps in the proper
sequence.
(a) Place the lens on a V-shaped stand.
(b) Place the object at ( 2 F_{1} )
(c) Place the object between ( 2 F_{1} ) and ( F_{1} )
(d) Determine the focal length of the lens by focusing the lens to a distant object like a tree.
(e) Adjust the position of the screen behind the lens to obtain a clear image and study the nature of the image.
(f) Mark the positions of ( F_{1}, 2 F_{1}, F_{2} )
and ( 2 F_{2} )
(g) Focus the lens to a distant object like a tree.
(h) Place the object just behind ( 2 F_{1} )
(i) Place the object at ( boldsymbol{F}_{1} )
(j) Place the object between ( F_{1} ) and optic centre of the lens and observe that the image formed is virtual.
( A cdot ) a f ( d h ) e ( g ) e b e ce ej
B. b a fhe gec
c. a dfge he bece iej
D. a df ge he cebeje
12
94Which of the following shows the bending of light from rarer (R) into denser (D) medium?
( A )
в.
c.
D.
12
95Focal length of a spherical mirror is ( 200 mathrm{cm} . ) What will be its radius of
curvature?
A . ( 100 mathrm{cm} )
B. ( 25 mathrm{cm} )
( c .50 c m )
D. ( 400 mathrm{cm} )
12
96What is the formula for refraction
through spherical Lens when the refractive index of the medium on two
sides of lens are different?
12
97A concave lens of focal length ( 5 mathrm{cm} ) is used as a simple microscope. The image is formed at the least distance of
distinct vision. Calculate the angular magnification.
12
98A convex lens is immersed in a liquid,
whose refractive index is equal to the
refractive index of the material of the
lens. Then its focal length will
A. Decrease
B. Become zero
c. Become infinite
D. Increase
12
99The index of refraction of diamond is
2.0. The velocity of light in diamond in cm/s is –
A ( .6 times 10^{10} )
В. ( 2 times 10^{10} )
C ( .3 times 10^{10} )
D. ( 1.5 times 10^{10} )
12
100What can you say about the angle of deviation in such a situation?
A. Angle of deviation is minimum.
B. Angle of deviation is maximum.
c. Angle of deviation is constant.
D. None of the above
12
101How can you determine the focal length of a convex lens experimentally. Draw a
rough diagram.
12
102State whether given statement is True
or False

When a point object is at the principal focus of a convex lens, it forms a parallel beam of light after refraction.
A. True
B. False

12
103The power of a lens is ( +2.0 D . ) Find its focal length and state the kind of the lens.
A. Convex, ( 50 mathrm{cm} )
B. Convex, ( 200 mathrm{cm} )
c. concave, ( 50 mathrm{cm} )
D. Concave, ( 100 mathrm{cm} )
12
104A plane mirror makes an angle of ( 30^{circ} ) with the horizontal. If a vertical ray
strikes the mirror, find the angle between the mirror and the reflected ray
( ? )
12
105Write Newton’s formula for refraction of
Light through a lens. Explain the meaning of symbols used.
12
106Which of the following occurs in
scattering?
A. Light is reflected back in the original direction.
B. Light is split into its spectrum.
C. Photons in the light wave are absorbed by the particles.
D. Absorption and re-emission of light energy by small particles.
12
107One end of a cylindrical rod is grounded to a hemispherical surface of radius
( R=20 m m . ) It is immersed in water of
refractive index ( 1.33 . ) If the refractive
index of the hemisphere is ( 1.5 . ) Find the position of an image of an object placed on the axis of the rod inside water at
( 10 mathrm{cm} ) from the pole.
12
108Braille system is categorized under:
A. non optical aids
B. optical aids
C. both ( A ) and ( B )
D. none of these
12
109A beam of light is incident on a glass slab ( (mu=1.54) ) in a direction as shown
in the figure. The reflected light is
analysed by a polaroid prism. On
rotating the polaroid (take, ( tan 57^{0}= )
1.54)
12
110Why do humans have two eyes?
a. The view field is increased up to ( 180^{circ} )
b. Better detection of faint objects
c. 3 dimensional view
d. More accurate estimation of distance
( A cdot a, b ) and ( d )
B. c and d
( c cdot a, c ) and ( d )
D. All of the above
12
111A defective eye cannot see close objects clearly because their image is formed:
A. On the eye lens
B. Between eye lens and retina
c. on the retina
D. Beyond retina
12
112Spherical mirror with reflecting surface curved inwards is called
A. convex mirror
B. concave mirror
c. curved mirror
D. None of these
12
113ldentify the wrong description of the
given figures
A . 1 represents far sightedness
B. 2 is correction for short sightedness
c. 3 represent far sightedness
D. 4 represents correction for far sightedness
12
114Find the correct statements related to
the image formed by the plane mirror form the given below.
A. The image formed is laterally inverted, virtual and erect
B. The size of the image is equal to the size of the object.
C. The object distance from the plane mirror is equal to the image distance from the plane mirror
D. All the above
12
115Rainbow is due to
This question has multiple correct options
A. scattering of light
B. refraction of light
C . dispersion
D. total internal reflection of light
12
116When the object is at focus of a concave mirror, the image is formed at
A. focus
B. centre of curvature
c. within focus
D. infinity
12
117At what distance from a convex lens of
focal length ( 0.15 m ) must an object be
placed so that the image must be twice the size of the object, when the image is
a) real
b) virtual
12
118A thin lens has a focal length of ( -50 c m ) What kind of lens is it?
A. concave lens
B. Convex lens
c. Concano convex lens
D. None
12
119An object of height ( 6 mathrm{cm} ) is placed perpendicular to the principal axis of a concave lens of focal length ( 5 mathrm{cm} . ) Use lens formula to determine the position, size and nature of the image if the distance of the object from the lens is 10
( mathrm{cm} )
12
120A transparent solid cylindrical rod has a refractive index of ( frac{2}{sqrt{3}} . ) It is surrounded by air. A light ray is incident at the mid-
point of one end of the rod as shown in
the figure. The incident angle ( theta ) for
which the light ray grazes along the wall
of the rod is –
( mathbf{A} cdot sin ^{-1}left(frac{1}{2}right) )
B. ( sin ^{-1}left(frac{sqrt{3}}{2}right) )
( c cdot sin ^{-1}left(frac{2}{sqrt{3}}right) )
D ( cdot sin ^{-1}left(frac{1}{sqrt{3}}right) )
12
121Consider the following statements ( A ) and ( mathrm{B} ) and identify the correct choice
A) For a given value of angle of incidence, the angle of deviation produced by a prism increases with increasing of refractive index of the prism
B) Angle of deviation produced by a thin prism is independent of angle of incidence
A. A is true and B is false
B. A is false and B is true
c. A and B are true
D. A and B are false
12
122When light passes from air to glass, it experiences a change of:
A. speed only
B. wavelength and speed
c. frequency only
D. frequency and speedd
12
123A spherical mirror whose inner hollow surface is the reflecting surface is a –
A. convex mirror
B. concave mirror
c. convex lens
D. concave lens
12
124If the angle of incidence is ( 50^{circ} )
then calculate the angle between the incidence ray and the reflected ray.
A .50
B. 100
c. ( 130^{circ} )
D. ( 80^{circ} )
12
125Find the angle of incidence and angle of
reflection from the diagram.
A ( cdot 45^{circ}, 40^{circ} )
B . ( 55^{circ}, 55^{circ} )
( mathbf{c} cdot 60^{circ}, 60^{circ} )
D. ( 30^{circ}, 30^{circ} )
12
126If the incident ray falls on a surface normally, then the angle of reflection is degree
A . 90
B.
( c . ) 30
D. 60
12
127State whether the following statement
is true or false:
The velocity of light is different in different media.
12
128A projector lens has a focal length 10
( mathrm{cm} . ) It throws an image of a ( 2 mathrm{cm} times 2 mathrm{cm} )
Slide on a screen 5 meter away from the
lens. Find
(i) The size of the picture on the screen
and
(ii)ratio of illuminations of the slide and
of the picture on the screen.
12
129A compound lens is made of two lenses
in contact having power ( +12.5 D ) and ( -2.5 D . ) An object is placed at ( 15 mathrm{cm} ) from compound lens. Find the position of image formed
( mathbf{A} cdot 60 mathrm{cm} )
B. ( 30 mathrm{cm} )
c. ( 15 mathrm{cm} )
D. ( 45 mathrm{cm} )
12
130Name any two defects vision which can
be corrected by any of spectacles.
12
131A needle of length ( 5 mathrm{cm}, ) placed ( 45 mathrm{cm} ) from a lens form an image on a screen placed ( 90 mathrm{cm} ) on the other side of the
lens. The type of lens and its focal length
are :
A. convex, 30 cm
B. concave, 30 cm
c. convex, ( 60 mathrm{cm} )
D. concave, 60 cm
12
132Define the following:
(a) Total internal reflection
(b) Diffraction of light
(c) Refraction of light
12
133What is seen on the screen when the
flame is very close (at about 5cm) to
the lens?
12
134Internal reflections of light is prevented
in human eye by:
A . iris
B. pupil
c. choroid
D. blind spot
12
135Aqueous humour is a
and vitreous humour is
( a )
A. transparent jelly, viscousfluid
B. transparent jelly, watery fluid
c. viscous fluid, viscous fluid
D. viscous fluid, transparent jelly
12
136A lens is made of flint glass (refractive index ( =1.5 ) ). When the lens is immersed in a liquid of refractive index 1.25, the focal length:
A. Increases to a factor of 1.25
B. Increases to a factor of 2.5
c. Increases to a factor of 1.2
D. Decreases to a factor of 1.2
12
137If a mirror has focal length of ( +15 mathrm{cm} )
then it is a
A. Convex mirror
B. Concave mirror
c. Plane mirror
D. None of these
12
138A girl viewed an object and found that it is not clearly visible to her. It was found that the image was formed by her eye lens ( 3 mathrm{cm} ) away from the pupil of her
eyes.The girl can correct this defect by using a:
A. concave lens
B. convex lens
c. bi-focal lens
D. plano-convex lens
12
139Correct mirror formula is:
A ( cdot frac{1}{v}-frac{1}{u}=frac{1}{f} )
в. ( frac{1}{v}+frac{1}{u}=frac{1}{f} )
c. ( frac{1}{v}-frac{1}{u}=frac{1}{-f} )
D. ( frac{1}{v}+frac{1}{u}=frac{1}{-f} )
12
140What is the function of the iris in
human eye?
A. Iris restricts the light to pass through the eye over to the retina.
B. Iris provides protection to the eye from microorganisms.
C. Iris controls the size of the pupil and hence the amount of light entering the eye.
D. Iris allows colour detection in eye.
12
141Reflection is the ( _{text {十一一一一一一一一一 }} ) Ilight
off a surface.
12
142(a) Draw and label the diagram given :
(i) Incident ray
(ii) Refracted ray
(iii) Emergent ray
(iv) Angle of reflection
(v) Angle of deviation
(v) Angle of emergence
(b) The refractive index of diamond is
2.42. What is the meaning of this statement in relation to speed of light?
12
143In case of a virtual and erect image, the magnification created by the mirror is
A. positive
B. negative
c. unity
D. infinity
12
144Fill in the blank.
The reflection of sunlight takes place the water droplets to
form a rainbow.
A . outside
B. inside
c. beside
D. below
12
145A light ray makes an angle of incidence
( 60^{circ}, ) when it falls on a plane reflecting
sheet
The angle of reflection will be.
A ( cdot 60^{circ} )
B. ( 30^{circ} )
( c cdot 45^{circ} )
D. ( 90^{circ} )
12
146Focal length of a lens is ( 50 mathrm{cm} ). Its power would be:
A. 50 dioptres
B. 2 dioptres
c. 20 dioptres
D. None of these
12
147Identify the mirrors
a)
( mathbf{b}) )
A. ( a= ) Convex mirror ( b= ) Concave mirror
B. ( a= ) Concave mirror ( b= ) Convex mirror
C ( . a= ) Concave mirror ( b= ) Concave mirror
D. ( a= ) Convex mirror ( b= ) Convex mirror
12
148A girl with two normal eyes wants to see the full width of her face using a plane
mirror. The eye to eye and ear to ear distances of her face are 4 inch and 6
inch respectively. The minimum width of the required mirror is:
A. 1 inch
B. 2 inch
( c .2 .5 ) inch
D. 5 inch
12
149When a ray of light passes from an optically more dense medium to a less dense medium, it:
A. goes undeviated
B. bends towards the normal
c. bends away from the normal
D. none of these
12
150In the displacement method, a convex lens is placed in between an object and a screen. If one of the magnification is 3 and the displacement of the lens between the two positions is ( 24 mathrm{cm}, ) then the focal length of the lens is:
A . ( 10 mathrm{cm} )
B. ( 9 mathrm{cm} )
( c cdot 6 mathrm{cm} )
D. ( 16 / 3 mathrm{cm} )
12
151An object is placed at a distance of ( boldsymbol{f} / mathbf{2} )
from a convex lens. The image will be
A. At one of the foci, virtual and double its size
B. At ( 3 f / 2 ), real and inverted and erect
c. At ( 2 f ), virtual and inverted
D. At ( f ), real and inverted
12
152If the angle of a prism is ( 60^{circ} ) and angle
of minimum deviation is ( 40^{circ}, ) then the
angle of refraction will be
A ( .30^{circ} )
B . ( 4^{circ} )
( c cdot 3^{circ} )
D. ( 1.5^{circ} )
12
153Find magnification for lens.
( A )
B.
( c cdot 7 )
D. 12
12
154Why does the sky appears dark instead
of blue to astronauts?
12
155A divergent lens produces an image of magnification 0.5 when the object distance of ( 10 mathrm{cm} . ) Find the focal power
of the lens (in diopters)
12
156State whether true or false:
A concave lens, if kept at a proper distance from an object, can form its real image.
A. True
B. False
12
15766. The focal lengths of the objective and the eye-piece of a
compound microscope are 2.0 cm and 3.0 cm respectively,
The distance between the objective and the eye-piece is
15.0 cm. The final image formed by the eye-piece is at
infinity. The two lenses are thin. The distances in cm of the
object and the image produced by the objective measured
from the objective lens are respectively
(a) 2.4 and 12.0
(b) 2.4 and 15.0
(c) 2.3 and 12.0 (d) 2.3 and 3.0
12
158Think about the objects which act as a
concave or convex mirrors in your surroundings. Make a table and display
it in your class room.
12
159Draw a ray diagram for concave mirror when object is placed between focus
and centre curvature. Also write
position, nature and size of image.
12
160A small piece of wire bent into an ( boldsymbol{L} )
shape, with upright and horizontal portions of equal lengths, is placed with the horizontal portion along the axis of
the concave mirror whose radius of
curvature is ( 10 mathrm{cm} ). If the bend is ( 20 mathrm{cm} )
from the pole of the mirror,then the ratio
of the lengths of the images of the upright and horizontal portions of the wire is
A. 1: 2
B. 3: 1
c. 1: 3
D. 2: 1
12
161The bottom of glass beaker is made of a
thin equiconvex lens having bottom
side silver polished as shown in fig. Now the water is filled in the beaker up to a
height of ( h=4 m . ) The image of point
object floating at middle point of beaker at the surface of water coincides with it.
Find out the value of radius (in ( mathrm{m} ) ) of
curvature of lens. ( left(a boldsymbol{mu}_{boldsymbol{g}}=mathbf{3} / mathbf{2},_{boldsymbol{a}} boldsymbol{mu}_{boldsymbol{w}}=right. )
( mathbf{4} / mathbf{3}) )
12
162Four students showed the following
traces of the path of a ray of light
passing through a rectangular glass
slab

The trace most likely to be correct is
that of student
( A )
B. II
c. III
D. IV

12
163When white light is passed through prism and glass slab separately then
we get seven colours as emergent ray in former while same white light in latter.
As both are made up of same glass but why getting different results?
12
164Answer the following. State the function of iris and ciliary muscles in human eye.12
165Find ( Q 1 ) and ( Q 2 )12
166The light reflected back into the denser medium when a ray of light passes from a denser to a rarer medium, is said to
be ( ldots )
A. Totally relfected
B. Totally refracted
c. Internally reflected
D. Internally refracted
12
16728. The velocity of light in a medium is half its velocity in air.
If a ray of light emerges from such a medium into air, the
angle of incidence, at which it will be totally internally
reflected, is
(a) 15°
(b) 30°
(c) 45°
(d) 60°
12
168Due to refraction,
A. Image in the plane mirror is clear
B. Polished black surfaces shine
C. speed of light is constant in all mediums
D. A glass sphere appears attractive
12
169An object is placed at ( 40 mathrm{cm} ) from the optic centre of a convex lens on its
principal axis. if the focal length of the lens is ( 24 mathrm{cm} ), find how far from the lens
the screen should be placed to obtain a well-defined image.
A . ( 48 mathrm{cm} )
B. 38 cm
( c .50 mathrm{cm} )
D. ( 60 mathrm{cm} )
12
170Two thin lenses have combined power of 10 ( D ). When separated by ( 20 mathrm{cm} ) their
equivalent power is 6.25 D.Their
individual powers in ( D ) are
A . 3.5 and 6.5
B. 5 and 5
c. 7.5 and 2.5
D. 9.0 and 1
12
171An under-water swimmer cannot see
very clearly even in absolutely clear water because of:
A. Absorption of light in water
B. Scattering of light in water
c. Reduction of speed of light in water
D. Change in the focal length of eye lens.
12
172Image of an object is seen in a plane
mirror, the distance from the mirror to
the image depends on:
A. the distance of the observer from the mirror
B. the distance of the object from the mirror
c. the distance of both the observer and the object to the mirror
D. the thickness of the mirror
12
173A diverging lens of focal length ( f_{1} ) is placed in front of and coaxially with a
concave mirror of focal length ( f_{2} ). Their
separation is d. A parallel beam of light incident on the lens returns as a
parallel beam from the arrangement. Then
This question has multiple correct options
A. the beam diameters of the incident and reflected beams must be the same
в. ( d=2left|f_{2}right|-left|f_{1}right| )
c ( cdot d=left|f_{2}right|-left|f_{1}right| )
D. if the entire arrangement is immersed in water, the conditions will remain unaltered
12
174Height of the image of an object on an principal axis produced by a convex lens is double the focal length of lens is
( 20 c m, ) then image distance from the lens is:
( mathbf{A} cdot 10 mathrm{cm} )
B. ( 30 mathrm{cm} )
( mathbf{c} cdot 40 mathrm{cm} )
D. Both (1) and (2)
12
175State whether true or false:
The principal focus of a spherical mirror lie midway between the pole and centre of curvature.
A. True
B. False
12
176Why red colour is given to signals to be viewed from a distance?12
177A clock fixed on a wall shows time 04:
( 25: 37 . ) What time will its image in a
plane mirror show?
A .07: 43: 32
B. 07: 43: 32
c. 07: 35: 23
D. 43: 27: 36
12
17824. A thin convex lens made from crown glass
has focal length f. When it is measured in two different
liquids having refractive indices
, it has the
focal lengths f, and f, respectively. The correct relation
between the focal lengths is
(a) f2 > f and f, becomes negative
(b) both fi and f become negative
(c) fi=f2 f and f becomes negative (JEE Main 2014)
12
179Certain plane wavefronts are shown in
figure. The refractive index of medium
is
4
B.
( c cdot 1.5 )
D. cannot be determined
12
180Inner side of the cylindrical tube of a periscope is blackened to avoid:
A. unwanted refraction
B. unwanted reflection
c. diffusion
D. both a and
12
181An object is seen first in red light and
then in violet light through a simple microscope. In which case is the magnification larger?
12
182If the minimum deviation produced by a prism of refracting angle 60 is ( 30, ) then calculate the refractive index of the
material of the prism.
A .2
B. 1.414
c. ( sqrt{13} )
D. 4
12
183An incident ray strikes a plane mirror at
an angle of incidence of ( 40^{circ} . ) What is the
percentage decrease in the angle of reflection if the incident ray moves to an
angle of incidence of ( 30^{circ} ? )
A . ( 10 % )
B . 20%
c. ( 25 % )
D. 30%
12
184One can not see through fog because:
A. fog absorbed light
B. light is scattered by the droplets in fog
C. light surfers total reflection by the droplets in the fog
D. the refractive index of fog is in infinity
12
185Which prism surface will behave as
mirror?
12
186You are able to see in shaded areas,
such as under a tree, because light has undergone:
( A ). refraction
B. incident bending
c. a change in speed
D. diffused reflection
12
187(a) A student suffering from myopia is not able to see distinctly the objects
placed beyond ( 5 m . ) List two possible
reasons due to which this defect of
vision may have arisen. With the help of ray diagrams, explain
(i) why the student is unable to see distinctly the objects placed beyond ( 5 m ) from his eyes.
(ii) the type of the corrective lens used
to restore proper vision and how this defect is corrected by the use of this lens.
(b) If, in this case, the numerical value of the focal length of the corrective lens is ( 5 m ), find the power of the lens as per the new Cartesian sign convention.
12
188A linear object of size ( 1.5 mathrm{cm} ) placed at ( 10 mathrm{cm} ) from a lens of focal length ( 20 mathrm{cm} )
The optic centre of lens and the object
are displaced a distance ( Delta=0.5 mathrm{cm} ) as
shown in the figure. The magnification
of the image formed is ( mathrm{m} ) (Take optic centre as origin). The coordinates of
image of ( A ) and ( B ) are ( left(x_{1}, y_{1}right) ) and
( left(x_{2}, y_{2}right) ) respectively. Then

This question has multiple correct options
A ( cdotleft(x_{1}, y_{1}right)=(-20 c m,-1 c m) )
в. ( left(x_{2}, y_{2}right)=(-20 c m, 2 c m) )
( mathrm{c} cdot m=3 )
D. ( m=2 )

12
189Assertion: Diamond glitters brilliantly.
Reason: Diamond does not absorb
sunlight.
A. Both assertion and reason are true but the reason is the correct explanation of assertion
B. Both assertion and reason are true but the reason is
not the correct explanation of assertion
C. Assertion is true but reason is false
D. Both the assertion and reason are false
E. Reason is true but assertion is false
12
190Amount of light entering the eye is controlled by:
A. Iriss
B. Cornea
c. Pupil
D. crystalline lens
12
191A direct-vision prism is made out of
three prisms, each with a refracting
angle of ( phi=60^{circ}, ) attached to each other
as shown in Fig. Light of a certain
wavelength is incident on the first
prism. The angle of incidence is ( 30^{circ} ) and
the ray leaves the third prism parallel to
the direction of incidence. The refractive
index of the glass of the first and third
prisms is ( 1.5 . ) Find the refractive index of the material of the middle prism.
( (sqrt{6}=2.45) )
12
192Differentiate between regular and
diffused reflection. Does diffused
reflection mean the failure of the laws of
reflection?
12
193Give scientific reason:
Danger signals are red in color.
12
194A beam of light striking the surface of a
glass plate from the air as shown in
above figure.
If the angle between reflected beam and
refracted beam is 90 degree, Find out
the index of refraction of the glass?
( A cdot sin 55^{circ} )
B. ( frac{1}{sin 55^{circ}} )
c. ( frac{1}{sin 35^{circ}} )
D. ( frac{sin 55^{circ}}{sin 35^{circ}} )
E ( cdot frac{sin 35^{circ}}{sin 55^{circ}} )
12
195Fill in the blanks:
Rainbows are caused by the dispersion of white light in
A. raindrops
B. prism
c. glass slab
D. air
12
196The impression of an image on the brain for one sixteenth of a second is
called
12
197Two convex lenses have focal lengths 10
( mathrm{cm} ) and ( 40 mathrm{cm} . ) If a telescope has to be
made by using these two lenses
1. The distance between the lenses
should be ( 50 mathrm{cm} )
2. The distance between the lenses
should be ( 30 mathrm{cm} )
3. The magnifying power of this
telescope will be 5
4. An inverted image will be produced in this telescope Which two of the give are correct?
A. 1 and 4
B. 2 and 4
c. 1 and 3
D. 3 and 4
12
198A person wear normal spectacles in which the distance of glasses and eyes is approximately ( 2 mathrm{cm}, ) then power required is ( -5 D . ) If he wears contact
lens, then the required power is?
A . -5.2 D
B. -4.54 D
c. ( +5.2 mathrm{D} )
D. +4.7 D
12
199A convex lens of focal length ( 0.15 mathrm{m} ) is
made of a material of refractive index 2
When it is placed in a liquid, its focal length increases by ( 0.225 m . ) The refractive index of the liquid is
A ( cdot frac{7}{4} )
B. ( frac{5}{4} )
( c cdot frac{9}{4} )
D. ( frac{3}{2} )
12
200The following conditions are seen in which defect of vision?
a. The vision is clear up to a distance of
few meters
b. It may occur due to elongation of eyeball
c. The image of the object is formed in front of the retina
A. Myopia
B. Cataract
c. Presbyopia
D. Hypermetropia
12
201The least distance of distinct vision for
a young adult with normal vision is
about
A. ( 1 mathrm{m} )
B. 2.5 ( m )
c. ( 0.25 mathrm{m} )
D. 25 m
12
202Transparent front part of eye is:
A . pupil
B. cornea
( c ). iris
D. retina
12
203If the focal length of a convex mirror is
( 16 mathrm{cm}, ) what is its radius of curvature?
( A cdot 8 mathrm{cm} )
B. ( 16 mathrm{cm} )
c. ( 32 mathrm{cm} )
D. ( 10 mathrm{cm} )
12
204A hair dresser stand with her nose 20
( mathrm{cm} ) in front of a plane mirror for what distance must she focus her eyes in
order to see her nose in the mirror?
A. ( 50 mathrm{cm} )
B. 30 cm
( c .60 mathrm{cm} )
D. ( 40 mathrm{cm} )
12
205Light travels through a glass plate of
thickness ‘t’ and refractive index ‘n’. If c
is the velocity of light in vacuum, then the time taken by light to travel through the thickness of the plate will be
A ( cdot frac{n t}{c} )
B. ( frac{t}{n c} )
c. ( frac{t c}{n} )
D. ( frac{c}{n t} )
12
206A thin lens of refractive index 1.5 has a
focal length of ( 15 mathrm{cm} ) in air. When the
lens is placed in a medium of refractive
index ( 4 / 3, ) its focal length will becomes
( mathrm{cm} )
12
207A boy in front of mirror throws ball from right hand and catches with left hand.
The direction of image of ball as seen from image of boy is:
A. Right hand to left hand
B. Left hand to Right Hand
c. Right hand to Right Hand
D. Left Hand to Left Hand
12
208Draw a labeled sketch of the human eye.12
209Draw a ray diagram of reflecting type telescope and hence give the advantage of reflecting type telescope.12
210Three right angled prisms of refractive
indices ( n_{1}, n_{2} ) and ( n_{3} ) are fixed together
using an optical glue as shown in figure. If a ray passes through the prisms without suffering any deviation,
then
A ( . n_{1}=n_{2}=n_{3} )
B . ( n_{1}=n_{2} neq n_{3} )
c. ( 1+n_{1}=n_{2}+n_{3} )
D. ( 1+n_{2}^{2}=n_{1}^{2}+n_{3}^{2} )
12
211What happens to the speed of light
when it undergoes refraction in a
medium ? Hence define absolute
refractive index of a medium.
12
212Twinkling of stars is on account of
A. Large distance of stars and storms in air
B. Small size of stars
C. Large size of stars
D. Large distance of stars and fluctuations in the density of air
12
213Define critical angle and polarising angle what is the relation between the two angles?12
214Match the following
( begin{array}{lllll}text { List I } & & text { List II } & \ text { Adjustment } & & & \ text { of focal } & text { a } & text { Accommodation } \ text { length } & & & \ text { 2 } & begin{array}{l}text { distance of } \ text { distinct vision }end{array} & text { b } & text { Infinity } \ text { 3 } & begin{array}{l}text { Farthest point } \ text { of visibility }end{array} & text { c } & text { 25 cm } \ text { 4 } & begin{array}{l}text { Vision } \ text { impairment }end{array} & text { d } & text { Cataract }end{array} )
A . ( 1-b, 2-c, 3-a, 4-d )
B. 1-d, 2-c, 3-b, 4-a
c. ( 1- ) a, ( 2-c, 3-b, 4-d )
D. 1-c, 2-a, 3-d, 4-b
12
215The sum of the reciprocals of object distance and image distance is equal to the of a mirror.
A. focal length
B. reciprocal of the focal length
c. radius of curvature
D. reciprocal of the radius of curvature
12
216Mirage is an example of12
217Geometrical Optics
73. A Galileo telescope has an objective of focal length
100 cm and magnifying power 50. The distance between
the two lenses in normal adjustment will be
(a) 98 cm
(b) 100 cm
(c) 150 cm
(d) 200 cm
12
218Consider an optical system placed in
water ( (mu=4 / 3) ) PQRS is a hollow glass
slab filled with air ( (mu=1) ) This slab is
kept on the principle axis of a lens in
such a way that surface PS makes an
angle ( theta ) with the axis of the lens.
( left(0<theta<180^{circ}right), ) then
This question has multiple correct options
A. for transmission of light takes place through slab ( theta_{min }=frac{pi}{2}-sin ^{-1}(0.75) )
B cdot for transmission of light through slab ( theta_{text {max }}=frac{pi}{2}+sin )
( -1(0.75) )
C. for ( x=50 mathrm{cm} ) final image is at ( 3 mathrm{m} ) distance from 0
D. for ( x=100 mathrm{cm} ) final image is at ( 3 mathrm{m} ) distance from 0
12
219When the angle of incidence of a ray is
greater than the critical angle, the refracted ray is in the same medium,
i.e., the light is totally reflected in the same medium. This is known as
A. Total internal reflection
B. Critical reflection
c. Mirage
D. Optical illusion
12
220The figure shows cross section of a
hollow glass tube of internal radius ( r )
external radius ( boldsymbol{R} ) and index of
refraction ( n . ) For two rays DE and ( A B C ) (in
which DE lies on ODE and DE is parallel
to BC), the separation ( r_{1} ) will be :
A ( cdot r_{1}=(n-1) R )
( mathbf{B} cdot r_{1}=n^{2} R )
( mathbf{c} cdot r_{1}=n r )
( mathbf{D} cdot r_{1}=n^{2} r )
12
221The image of an object is formed by a convex lens. When that object is placed beyond the focal length is –
A. Virtual and inverted
B. Virtual and magnified
c. Real and inverted
D. Real and magnified
12
222The field of view is maximum for
A. Plane mirror
B. Concave mirror
c. convex mirror
D. plano concave mirror
12
223Match the following A
( mathbf{A} )
1-b, 2-c, 3-a, 4-d
B. ( 1-c, 2-d, 3-b, 4-a )
c. ( 1-a, 2-c, 3-b, 4-d )
D. ( 1-c, 2-a, 3-d, 4-b )
12
224The image of a square hole in a screen illuminated by light is obtained on another screen with the help of a converging lens. The distance of the
hole from the lens is ( 40 mathrm{cm} ). If the area
of the image is nine times that of the
hole, the focal length of the lens is :
( mathbf{A} cdot 30 mathrm{cm} )
B. ( 50 mathrm{cm} )
c. ( 60 mathrm{cm} )
D. ( 75 mathrm{cm} )
12
225A bi-convex lens is formed with two
plano-convex lenses as shown in the figure. Refractive index n of the first
lens is 1.5 and that of the second lens is
1.2. Both curved surfaces are of the
same radius of curvature ( mathrm{R}=14 mathrm{cm} . ) For
this bi-convex lens, for an object
distance of ( 40 mathrm{cm}, ) the image distance will be
A. ( -280.0 mathrm{cm} )
B. ( 440.0 mathrm{cm} )
( c .21 .5 mathrm{cm} )
D. ( 13.3 mathrm{cm} )
12
226Fill up the blanks:
a) light sensitive screen of human
eye……………..
b) near sightedness is corrected
by
c) hypermetropia is corrected by…..
d) range of vision for a normal eye………….
( A cdot ) a. retina
b. concave lens
c. convex lens
d. ( 25 mathrm{cm} ) -infinity
B. a. cornea
b. convex lens
c. concave lens
d. ( 0-25 mathrm{cm} )
c. a. iris
b. converging lens
c. diverging lens
d. 0 -infinity
D. a. sclera
b. diverging lens c convex lens
d. infinity
12
227A biconvex lens made of
glass(refractive index 1.5 ) has two
spherical surfaces having radii 20cm and ( 30 mathrm{cm} . ) Calculate its focal length.
12
228Two refracting media are separated by
a spherical interface as shown in figure.
PP’ is the principle axis. ( mu_{1} ) and ( mu_{2} ) are
the refractive indices of medium of
incidence and medium of refraction
respectively. Then,
This question has multiple correct options
( mathbf{A} cdot ) if ( mu_{2}>mu_{1} ) then there cannot be a real image of real object
( mathbf{B} cdot ) if ( mu_{2}>mu_{1} ) then there cannot be a real image of virtual object.
( mathrm{C} cdot ) if ( mu_{1}>mu_{2} ) then there cannot be a virtual image of virtual object
D. if ( mu_{1}>mu_{2} ) then there cannot be a real image of real
object
12
229Assertion
In the absence of atmosphere the sky
would appear black.
Reason
Atmosphere scatters the light and
hence we get blue colour.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
230The image of an object is formed 3 times by a convex lens. On interchanging the positions of object and screen, what will be the
magnification in that case?
12
231A converging lens of focal length 6.25 ( mathrm{cm} ) is used as a magnifying glass. If near point of the observer is ( 25 mathrm{cm} ) from the eye and the lens is held close to the eye, then the magnification is :
( A cdot 4 )
B. 5
( c cdot 8 )
D. 10
12
232Figure shows three lenses of equal radii of curvature of the curved surfaces. the
ratio of focal lengths of ( mathrm{P}, mathrm{Q} ) and ( mathrm{R} ) is
A .1: 1: 1
B. 1:1:-1
( c )
D . – -1:2:-
12
233Focal length of the plano-convex lens is
( 15 mathrm{cm} . ) A small object is placed at ( A ) as
shown in the figure. The plane surface is silvered. The image will form at
A. ( 60 mathrm{cm} ) to the left of lens
B. ( 12 c m ) to the left of lens
( mathrm{c} .60 mathrm{cm} ) to the right of lens
D. ( 30 c m ) to the left of lens
12
234The focal length of an equiconcave lens is ( frac{3}{4} ) times of radius of curvature of its surfaces. Find the refractive index of the
material of the lens. Under what
condition will this lens behave as a
converging lens?
12
235A light ray, going through a prism with
the angle of prism ( 60^{circ}, ) is found to
deviate by ( 30^{circ} . ) What limit on the refractive index can be put from these
data ?
12
236The radii of curvature of the surfaces of
a double convex lens are ( 20 mathrm{cm} ) and 40
( mathrm{cm} ) respectively, and its focal length is ( 20 mathrm{cm} . ) What is the refractive index of
the material of the lens.?
A ( cdot frac{5}{2} )
B. ( frac{4}{3} )
( c cdot frac{5}{3} )
D. ( frac{4}{5} )
12
237Which of the following statement is/ are correct?
I. A person suffering from myopia can see distant obhects clearly.
II.. The bluish color of water in deep sea is only due to reflection of sky in water.
III. In vacuum, all the colored of the light
move with the same speed.
IV. At noon, the sun appears white as light is least scattered
A. I only
B. Il only
c. I and II only
D. III and IV only
12
238Assertion
A ray of light is incident from outside on
a glass sphere surrounded by air. This ray may suffer total internal reflection
at second interface.
Reason
If a ray of light goes from denser to rarer
medium, it bends away from the
normal.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
239Given is a diagram showing a defect of
human eye
Study it and answer the following questions:
Name the type of lens used to correct
the defect.
A. Convex
B. Concave
c. Bifocal
D. All of the above can be used
12
240Match the following
¡.
a. Back surface of eye where image is Cornea formed
ii. Pupil
b. Coloured part of eye
iii.
c. Membrane that refracts light and Retina protects the eye
¡V. Iris
d. Transparent opening of eye.Light passes through it
( A cdot ) i-c ,ii-d,iii-a,iv-b
B. i-a,ii-c,iii-b,iv-d
C . i-d,ii-a,iii-b,iv-c
D. i-b,ii-c,iii-d,iv-a
12
241An object ( 2 mathrm{cm} ) high is placed at a distance of ( 16 mathrm{cm} ) from a concave
mirror, which produces a real image 3 cm high. What is the focal length of the mirror?
A . ( -48 c m )
B. ( -36 c m )
( mathrm{c} .-63 mathrm{cm} )
D. -83 cm
12
242A line coming from point (3,4) is
reflected on a point A of x-axis and it
passes through point (1,8) then
coordinate of point A is
A ( cdot(7 / 3,0) )
В ( cdot(5,0) )
C ( cdot(29 / 3,0) )
D cdot ( (9 / 2,0) )
12
243The term refraction of light is best
described by:
A. The bending of light rays when they enter from one medium to another medium
B. Splitting of white light into seven colours when it passes through the prism
C. Bending of light round corners of obstacles and
apertures
D. Coming back of light from a bright smooth surface
12
244What is lateral shift? Establish relation
between focal length and radius of curvature of a mirror.
12
24519. A car is fitted with a convex side-view mirror of focal
length 20 cm. A second car 2.8 m behind the first car is
overtaking the first car at a relative speed of 15 m/s. The
speed of the image of the second car as seen in the mirror
of the first one is
(a) 1/10 m/s
(b) 1/15 m/s
(c) 10 m/s
(d) 15 m/s (AIEEE 2011)
12
246A ( 5 c m ) long needle lies along the principal axis axis of a concave mirror
of focal length ( 20 mathrm{cm} ) in such a way that
the end closer to the pole is ( 40 mathrm{cm} ) from
it. Find the length of the image of the needle formed by the mirror.
12
247Why do we study the Dispersion
phenomenon using a glass prism and
not a glass slab?
A. Light doesn’t undergo any deviation inside a glass slab; so cannot be used to study Disprsion
B. All of the dispersion that takes place at the first interface is exactly reversed at the second parallel surface, ‘undoing’ the effect of the first interface.
C. Dispersion occurs only in prism and not in glass slab
D. None of the above
12
248A simple telescope used to view distant objects has eyepiece and objective lens
of focal lengths ( f_{e} ) and ( f, ) respectively.
Then
12
249When all the parallel rays reflected from a mirror are parallel, the reflection is known as:
A . regular reflection
B. irregular reflection
c. diffused reflection
D. none of these
12
250Write short notes on dispersion of light.12
251Which material should be chosen to
make the concave mirrors of a high resolution telescope so that it can also withstand temperature variations?
A. Quartz
B. Flint glass
c. crown glass
D. combination of Flint and Silica
12
252Which of the following ray diagram is
correct?
( A )
B.
( c )
( D )
12
253In vacuum, to travel distance ‘d’, light takes time ‘t’ and in medium to travel
distance ( ^{prime} 5 d^{prime}, ) it takes time ‘T’. The
critical angle of the medium is.
A ( cdot sin ^{-1}left(frac{5 T}{t}right) )
в. ( sin ^{-1}left(frac{5 t}{3 T}right) )
c. ( sin ^{-1}left(frac{5 t}{T}right) )
D. ( sin ^{-1}left(frac{3 t}{5 T}right) )
12
254The diagram below a ray of light
incident on a glass prism. Calculate the
refractive index of the glass prism.
12
255The power of a lens is – ( 5 D )
(i) find its focal length.
(ii) name the type of lens.
12
256One half of a convex lens of focal length ( 10 mathrm{cm} ) is covered with a black paper. Can such a lens produce an image of a complete object placed at a distance of ( 30 mathrm{cm} ) from the lens? Draw a ray
diagram to justify your answer. A ( 4 mathrm{cm} ) tall object is placed perpendicular to its principal axis of a convex lens of focal length ( 20 mathrm{cm} . ) The distance of the object from the lens is 15 cm. Find the nature, position and the size of the image.
12
257We should look at sun or a powerful light directly. Is the statement True or
False
A. True
B. False
12
258In which of the following we see the phenomena of total internal reflection?
A. Rainbows
c. camera
D. Both a and
12
259A light ray of a single wavelength is incident on the prism. The emergent light is best described by a:
A. spectrum of component colours
B. laterally shifted ray of same wavelength.
c. light ray of same wavelength deviated by an angle.
D. light ray of different wavelength deviated by an angle
12
260The human eye part which can be used again and again for forming different images is called:
A . iris
B. pupil
c. cornea
D. retina
12
261A convex lens is used to form an image of an object on a screen. If the upper half of the lens is covered so that it becomes
opaque. Then :
A. only half of the image will be visible
B. the image position shifts towards the lens
c. the image position shifts away from the lens
D. the brightness of the image reduces
12
262Assertion
Fine particles in atmosphere scatter the
light of shorter wavelength more.
Reason
Sky appears blue.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
263During dispersion through prism, red light travels fastest and violet travels
slowest of all the seven colours. As a
result:
A. red bends the least and violet bends the most
B. red bends the most and violet bends the least
C. both red and violet bend the least of all colours
D. both red and violet bend the most of all colours
12
264An object and a screen are mounted on an optical bench and a converging lens is placed between them so that a sharp
image is received on the screen. The linear magnification of the image is 2.5 The lens is now moved ( 30 mathrm{cm} ) nearer
to the screen and a sharp image is again formed on the screen. The focal length of the lens is:
A . ( 14.0 mathrm{cm} )
в. ( 14.3 mathrm{cm} )
c. ( 14.6 mathrm{cm} )
D. ( 14.9 mathrm{cm} )
12
265The splitting of white light into several colours on passing through a glass prism is due to
( A ). refraction
B. reflection
c. dispersion
D. none of these
12
266The incident ray,reflected ray and the normal ray, all lie on the plane.
A. different
B. same
c. mutually perpendicular
D. orthogonal
12
267How the eye of a person suffering from myopia can be corrected? Explain with the help of ray diagram.12
268Sunlight can undergo internal reflection if it enters from:
A. glass to air
B. air to glass
c. air to water
D. water to glass
12
2691. An astronomical telescope has a large aperture to
(a) reduce spherical aberration.
(b) have high resolution.
(c) increases the span of observation.
(d) have low dispersion.
(AIEEE 2002)
12
270An object is kept ( 60 mathrm{cm} ) from a lens
gives a virtual image ( 20 mathrm{cm} ) in front of lens. What is the focal length of the lens? Is it converging lens or diverging lens?
12
271A compound microscope has an objective of focal length ( 1 mathrm{cm} ) and an
eyepiece of ( 4 mathrm{cm} . ) If the tube length is 20 ( mathrm{cm} . ) Then the magnification of the compound microscope is : (final image is at D
A . 145
B. 14.5
( c cdot 1.45 )
D. None of these
12
272For a prism kept in air, it is found that
for an angle of incidence ( 60^{circ} ), the angle
of refraction ( ^{prime} boldsymbol{A}^{prime}, ) angle of deviation ( ^{prime} boldsymbol{delta}^{prime} )
and angle of emergence ( ^{prime} e^{prime} ) become equal. The minimum angle of incidence of a ray that will be transmitted through the prism is
A . 1.73
в. 1.15
c. 1.5
D. 1.33
12
273How can we explain the reddish
appearance of sun at sunrise
or sunset?
A. Scattering of blue light is more than the scattering of red light
B. Scattering of red light is more than the scattering of blue light
C. Intensity of sun reduces during sunrise and sunset
D. Due to the view angle, it appears blue
12
274Where would an object be placed in a
medium of refractive index ( mu_{1}, ) so that
its real image is formed at equidistant from sphere (of radius ( mathrm{R} ) and refractive
index ( mu_{2} ) ) which is also placed in the
medium of refractive index ( mu_{1} ) as shown
in figure?
A ( cdotleft(frac{mu_{2}-mu_{1}}{mu_{2}+mu_{1}}right) R )
B ( cdotleft(frac{mu_{2}}{mu_{2}-mu_{1}}right) R )
c. ( left(frac{mu_{1}}{mu_{2}-mu_{1}}right) R )
D. ( left(frac{mu_{2}+mu_{1}}{mu_{2}-mu_{1}}right) R )
12
275The distance between an object and its real image formed by a convex lens
cannot be
A. greater than ( 2 f )
B. less than ( 2 f )
c. greater than ( 4 f )
D. less than ( 4 f )
12
276Effect of dispersion of light among the following is:
A . Mirage
B. Blue colour of the sky
c. Rainbow
D. Twinkling of stars
12
277A convex lens of focal length ( 15 mathrm{cm} ) is placed infront of a plane mirror at a distance ( 25 mathrm{cm} ) from the mirror. Where
on the optical axis and from the centre of the lens should a small object
be placed such that the final image coincides with the object?
A. ( 15 mathrm{cm} ) and on the opposite side of the mirror
B. ( 15 mathrm{cm} ) and between the mirror and the lens
c. ( 7.5 mathrm{cm} ) and on the opposite side of the mirror
D. ( 7.5 mathrm{cm} ) and between the mirror and the lens
12
278Can a concave lens form an image of size two times that of the object?
A. Yes
B. No
c. sometimes
D. None of these
12
279The image which can be obtained on a screen is called
A. a virtual image
B. a real image
c. either a real or a virtual image
D. neither a real nor a virtual image
12
280Two examples of non-luminous objects
are:
A. stars, the moon
B. a burning candle, a glowing bulb
c. the moon, a spoon
D. stars, a spoon
12
281Why is the ratio of the velocities of light
of wavelengths ( 4000 A ) and ( 8000 A ) in
vacuum ( 1: 1 ? )
12
282An object is placed at a distance of 40
( mathrm{cm} ) in front of a concave mirror of focal
length ( 20 mathrm{cm} . ) The image produced is:
A. real, inverted and smaller in size
B. real, inverted, and of same size
c. real and erect
D. virtual and inverteo
12
283Assertion
The minimum distance between an
object and its real image formed by a convex lens is ‘2 ( f^{prime} )
Reason
The distance between object and its
real image is minimum when its
magnification is one.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is incorrect but Reason is correct
D. Both Assertion and Reason are incorrect
12
284Light is
A. An electromagnetic radiation
B. A transverse wave
c. Massless
D. All of the above
12
285If the angle between incident ray and
normal is ( 30^{circ}, ) choose the correct option:
A. Angle between incident ray and mirror ( =60^{circ} )
angle between reflected ray and mirror ( =60^{circ} )
Angle between normal and the mirror ( =90^{circ} )
B. Angle between incident ray and mirror ( =30^{circ} )
angle between reflected ray and mirror ( =30^{circ} )
Angle between normal and the mirror ( =30^{circ} )
C. Angle between incident ray and mirror ( =120^{circ} )
angle between reflected ray and mirror ( =30^{circ} )
Angle between normal and the mirror ( =30^{circ} )
D. Angle between incident ray and mirror ( =60^{circ} )
angle between reflected ray and mirror ( =30^{circ} )
Angle between normal and the mirror ( =120^{circ} )
12
286What is scattering of light?12
287How will you use two identical prisms so that a narrow beam of white light incident on one prism emerges out of the second prism as white light?
A. Just put them side by side.
B. one placed on top of the other
c. one placed inverted with respect to the other.
D. none of these.
12
288( overrightarrow{boldsymbol{E}} times overrightarrow{boldsymbol{B}} ) equals to12
289( frac{sin i}{sin r}=dots dots )
( mathbf{A} cdot mathbf{1} )
B. 2
c. constant
D. Variable
12
290The focal length of a plane mirror is
A. positive
B. negative
c. zero
D. infinite
12
291Assertion
Critical angle of light passing from glass to air is minimum for violet color.
Reason

The wavelength of blue light is greatest to the light of other colors.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect

12
292The refractive index of a medium:
( mathbf{A} cdot ) is defined with respect to another medium
B. is an absolute constant for a medium
C. depends on the frequency of the light in the medium
D. is more for higher intensity of light ray
12
293The near point of a normal human eye is
A ( .25 m )
в. ( 17 m )
( c .1 m )
D. ( 25 mathrm{cm} )
12
294The image of an object formed by a
convex lens is of the same size as the
object. If the image is formed at a distance ( 50 mathrm{cm} ) from the lens at what distance from the lens is the object
placed? Find the focal length and power
of the used.
12
295Reflection can occur on
A. Transparent surfaces
B. Translucent surfaces
c. Opaque surfaces
D. ( B ) and ( c )
12
296A point source ( S ) is placed at a distance
of ( 15 mathrm{cm} ) from a converging lens of focal
length ( 10 mathrm{cm} ) on its principal axis. Where should a diverging mirror of focal length ( 12 c m ) be placed so that a real image is formed on the source itself?
12
297A child is standing in tront ot a straight plane mirror. His father is standing
behind him, as shown in the fig. The
height of the father is double the height
of the child. What is the minimum
length of the mirror required so that the
child can completely see his own image
and his fathers image in the mirror?
Given that the height of father is ( 2 H )
( mathbf{A} cdot H / 2 )
B. ( 5 H / 6 )
c. ( 3 H / 2 )
D. None of these
12
298What is the far point of a normal human
eyes?
12
299A crack in a glass vessel often shines
like a mirror because of
A. Total reflecting surface
B. Reflection
c. Refraction
D. All
12
300When a wave travels from one medium
to another, the quantity which will not change is its
A. Amplitude
B. Velocity
c. Frequency
D. Intensity
12
301The radius of curvature of a spherical mirror is :
A. equal to half its focal length
B. equal to one-fourth of its focal length
c. equal to its focal length
D. twice its focal length
12
302Reflection is the ( ldots ). Of light off a surface.
A. Bouncing
B. hitting
c. firing
D. all
12
303I ne retractıve index of the materıal of a
concave lens is ( mu . ) It is immersed in a
medium of refractive index ( mu_{1} . A )
parallel beam of light is incident on the
lens. The path of the emergent rays
when ( mu_{1}>mu ) is :
( mathbf{A} )
B.
( mathbf{c} )
D.
12
304Assertion
When a plane wave passes through a thin prism, the emerging wavefront gets titled.
Reason
Speed of light is less in glass than in air.
A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true and reason is not the correct explanation of assertion.
c. If assertion is true but reason is false
D. If both assertion and reason are false
12
305What happens when a ray of light is
made to fall on a mirror along the
normal?
A. The ray that comes after reflection makes ( 60^{circ} ) with the mirror
B. The ray that comes after reflection will be parallel to the mirror
c. The ray after reflection retraces its path.
D. After reflection, the ray does not come back
12
306When the object is placed ( 4 mathrm{cm} ) from the objective of microscope, the final image formed coincides with the object. The final image is at the least distance of distinct vision ( (24 mathrm{cm}) . ) If the focal
length of eye piece is ( 8 mathrm{cm} ) then the focal length of objective is
A . ( 3.25 mathrm{cm} )
B. ( 2 c m )
( mathrm{c} .3 .9 mathrm{cm} )
D. ( 4.2 mathrm{cm} )
12
307In displacement method, the distance
between object and screen is 96 cm.
The ratio of lengths of two images
formed by a converging lens placed
between them is ( 4 . ) Then
This question has multiple correct options
A. Ratio of the length of object to the length of shorter image is 2
B. Distance between the two positions of the lens is ( 32 mathrm{cm} )
C. Focal length of the lens is ( 64 / 3 mathrm{cm} )
D. When the shorter image is formed on screen, distance of the lens from the screen is ( 32 mathrm{cm} )
12
308When an object is placed at a distance of ( 60 mathrm{cm} ) from a convex mirror, the magnification produced is 1/2. Where should the object be placed to obtain a magnification of 1/3?12
309A ray is incident at an angle of incidence on one surface of a prism of
small angle ( A ) and emerges normally from the opposite surface. If the refractive index of the material of the
prism is ( mu, ) the angle of incidence ( i ) is
nearly equal to :
( A cdot A / mu )
в. ( A / 2 mu )
c. ( mu / A )
D. ( mu A )
12
310Why is a normal eye not able to see
clearly the objects placed closer than 25
( mathrm{cm} ? )
12
311Which of the following lens is used to minimise myopia?
A. Convex lens
B. Concave lens
c. Cylindrical lens
D. Planar lens
12
312( A 16 mathrm{cm} ) long pencil is placed as shown
in figure. The central point ( C ) is ( 45 mathrm{cm} ) away from a ( 20 mathrm{cm} ) focal length lens and ( 15 mathrm{cm} ) above the optic axis. Find the length of image.
A . ( 14.2 mathrm{cm} )
B. ( 12.3 mathrm{cm} )
( c .17 .1 mathrm{cm} )
D. ( 4.5 mathrm{cm} )
12
313Describe the compound microscope on the following headings
(i) Labelled Ray diagram of formation of image.
(ii) Magnifying power when final image is formed at least distance of distinct
vision.
12
314When light passes through prism it is :
A. Deviated
B. Deviated and dispersed
C . Reflected
D. Laterally Displaced
12
315Out of the following, select the correct
statements:
This question has multiple correct options
A. Mirage and looming take place in hot places
B. An object is not visible when its refractive index is unity
C. On increasing the angle of incidence, the angle of deviation also increases
D. During hot summer days, the trees and other tall objects seem to be quivering because the density of air changes in and irregular way
12
316Obtain relation when object distance
varies in a convex lens of focal length ( mathrm{f} )
12
317Why is it difficult to read from image of
a book in plane mirror?
A. Due to lateral inversion
B. Due to scattering
c. Due to vertical inversion
D. Due to loss on reflection
12
318A ( 2.0 c m ) object is placed ( 15 c m ) in front
of a concave mirror of focal length ( 10 mathrm{cm} )
What is the size and nature of the
image?
A. ( 4 c m ), real
B. ( 4 mathrm{cm} ), virtual
c. ( 1.0 mathrm{cm} ), real
D. None of these
12
319The angle made by incident ray of light with the reflecting surface is called
A. Glancing angle
B. Angle of incidence
c. Angle of deviation
D. Angle of refraction
12
320Two plano-concave lenses of glass of refractive index 1.5 have radii of
curvatures ( 20 mathrm{cm}, 30 mathrm{cm} . ) They are placed in contact with curved surface towards each other and the space between them is filled with a liquid of
refractive index ( 4 / 3 . ) The focal length of
the system is :
( mathbf{A} cdot 48 mathrm{cm} )
в. ( 72 mathrm{cm} )
( mathbf{c} cdot 12 c m )
D. ( 24 c m )
12
321The power of a lens having a focal length of ( 1 mathrm{cm} ) is :
( A cdot 1 D )
в. ( 10 D )
c. ( frac{1}{10} D )
D. ( 100 D )
12
322Based on this observation, state the
conclusion which can be drawn about
the constituents of white light.
12
323Consider an equiconvex lens of radius
of curvature ( boldsymbol{R} ) and focal length ( boldsymbol{f} ). If ( boldsymbol{f}> )
( R, ) the refractive index ( mu ) of the material
of the lens.
A. Is greater than zero but less than 1.5
B. Is greater than 1.5 but less than 2.0
c. Is greater than 1.0 but less than 1.5
D. None of these
12
324Assertion: The setting sun appears to be red.
Reason: Scattering of light is directly proportional to the wavelength.
A. both assertion and reason are true but the reason is the correct explanation of assertion
B. both assertion and reason are true but the reason is not the correct explanation of assertion
c. assertion is true but reason is false
D. both the assertion and reason are false
E. reason is true but assertion is false
12
325A light ray falls on a mirror and deviates
by ( 30^{circ}, ) then the angle of incidence will
be:
A .75
B. ( 60^{circ} )
( c cdot 90 )
D. 180
12
326Two thin plano-convex lenses each of
focal length ( f ) are placed as shown in
the figure. The ratio of their effective
focal lengths in the three cases is
(i)
(ii)
A .1: 2: 3
B. 1: 2: 1
c. 1: 1: 1
D. 3: 2: 1
12
327Show that the minimum size of a plane
mirror required to see the full image of
an observer is half the size of that
observer.
12
328The change in focal length of an eye lens is caused by the action of
A. pupil
B. retina
c. ciliary muscles
D. iris
12
32983. A convex lens of focal length
10 cm is painted black at the o
2 mm
middle portion as shown in
figure. An object is placed at a 20 cm
distance of 20 cm from the lens.
Then,
(a) only one image will be formed by the lens
(b) the distance between the two images formed by such
a lens is 6 mm
(c) the distance between the images is 4 mm
(d) the distance between the images is 2 mm
12
33071. A telescope of diameter 2 m uses light of wavelength
5000 Å for viewing stars. The minimum angular
separation between two stars whose image is just resolved
by this telescope is
(a) 4 x 104 rad (b) 0.25 x 10° rad
(c) 0.31 x 10 ºrad (d) 5.0 x 10- rad
12
331As the angle of incidence is increased
for a ray incident on a reflecting surface, the angle between the incident and reflected rays ultimately approaches:
A. zero
В . ( 45^{circ} )
( mathrm{c} cdot 90^{circ} )
D. ( 180^{circ} )
12
332A ray of light travelling in air is incident on the plane of a transparent medium.
The angle of incident is ( 45^{0} ) and that of
refraction is ( 30^{0} . ) The refractive index of
the medium with respect to air is:
A .2
в. ( frac{1}{sqrt{2}} )
c. ( 2 sqrt{2} )
D. ( sqrt{2} )
12
333Explain the reason which ray of light wil
be transmitted through the face ( A B ) the
refractive index of the prism for red,
green, blue are ( 1.39,1.42,1.47 ? sin )
( mathbf{7 1}=mathbf{4 6}^{circ}, sin . mathbf{7 0}=mathbf{4 4}^{circ}, operatorname{sin.67}=mathbf{4 2}^{circ} )
12
334A virtual image is
A. always erect
B. either erect or inverted
C . always inverted
D. neither erect nor inverted
12
335State whether true or false:
A concave lens forms a magnified or diminished image depending on the distance of object from it.
A. True
B. False
12
336A disease, in which eye lens become cloudy and the opaque lens is removed and a new artificial lens is inserted, is :
A. hypermetropia
B. astigmatism
c. cataract
D. near-sightedness
12
337When light is reflected from the a
spherical or curved surface:
A. the laws of reflections are followed
B. the laws of reflections are not followed
C. the laws of reflections may or may not be followed
D. one of the laws is followed, the other is not
12
338The magnification produced by a mirror is ( frac{1}{3} ) then the type of mirror is
A. Concave
B. convex
c. Plane
D. Planar
12
339A compound microscope consists of two convex lenses of focal length ( 2 mathrm{cm} )
and ( 5 mathrm{cm} . ) When an object is kept at a
distance of ( 2.1 mathrm{cm} ) from the objective, a virtual and magnified image is formed ( 25 mathrm{cm} ) from the eye piece. Calculate the magnifying power of the microscope.
12
340If angle of minimum deviation of a
prism is equal to refracting angle of the prism, then refractive index ( mu ) of
material of prism satisfies
A. ( 1<mu<sqrt{2} )
в. ( 2<mu<3 )
c. ( sqrt{2}<mu<2 )
D. ( 1<mu<sqrt{3} )
12
341Give a demonstration for total internal
reflection. What are the technological applications of total internal reflection
in nature? Briefly explain it.
12
342What will be the critical angle of water
if ( _{a} mu_{w}=frac{4}{3} )
A ( cdot 42 )
B . ( 49^{circ} )
( c cdot 22 )
D. 1
12
343The glancing angle of incidence is ( 10^{circ} ) What will be the glancing angle of reflection?
A ( .10^{circ} )
B. ( 80^{circ} )
c. ( 170^{circ} )
D. ( 60^{circ} )
12
344Assertion
A reflecting type telescope is preferred in astronomy
Reason
Weight of the mirrors are less as
compare the lenses.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
345When an object is placed on the principal axis of a convex lens at two different positions, it produces the images with magnification +2 and -4 respectively. How many times more away from the lens the image will be formed in the second position as compared to the first position?
( A cdot 2 )
B. 4
( c cdot 5 )
D. 10
12
346State whether true or false:
Rainbow is produced by the dispersion of sunlight by tiny raindrops in the air.
A. True
B. False
12
347A ( 4.0 mathrm{cm} ) high object is placed at a
distance of ( 60 mathrm{cm} ) from a concave lens
of focal length ( 20 mathrm{cm} . ) Find the size of the image.
12
348Explain the refection of transverse and longitudinal waves from a denser medium and a rarer medium.12
349A spherical mirror has radius of curvature equal to ( 50 mathrm{cm} ). Find the value
of focal length.
( mathbf{A} cdot 50 mathrm{cm} )
B. ( 30 mathrm{cm} )
( mathrm{c} cdot 25 mathrm{cm} )
D. ( 100 mathrm{cm} )
12
350The part of human eye which is sensitive to red, blue and green light is:
A. retina
B. lens
c. cornea
D. iris
12
351What is the other name
(a) myopia (b) hypermetropia?
12
352Rays of light fall on a glass plate of refractive index ( =sqrt{3} . ) If the
angle between refracted ray and
reflected ray is ( 90, ) the angle of incidence is :
A . 90
B . 45
c. 135
D. 60
12
353How do you find the focal length of a
concave mirror?
12
354Soap bubble appears coloured due to
the phenomenon of:
A. Total internal feflection
B. Interference by division of amplitude
c. Interference by division of wavefront
D. Diffraction of light
12
355(a) Name any two phenomena of light which cause the formation of a rainbow.
(b) A particular colour in the rainbow
makes an angle of ( 42.7^{circ} ) with the line of
vision. What is the colour?
(c) What will be the shape of a rainbow
when viewed from:
¡. Terrace of a house?
ii. Aircraft flying very high.
12
356A short linear object of length ( b ) lies along the axis of a concave mirror of
focal length ( f ) at a distance ( u ) from the pole of the mirror. The size of the image is approximately equal to:
( A )
[
bleft(frac{u-f}{f}right)^{frac{1}{2}}
]
в.
[
bleft(frac{u-f}{f}right)
]
( c )
[
bleft(frac{f}{u-f}right)^{frac{1}{2}}
]
D.
[
bleft(frac{f}{u-f}right)^{2}
]
12
357A soap bubble has a thickness of
( 100 n m ) and a refractive Index of 1.35
Given that the wavelength of red light is about ( 700 n m ) and that of blue light is
( 400 n m, ) what colour does the bubble appear to be at the point on its surface closest to an observer when it is
illuminated by white light?
A. White
B. Black
c. Red
D. Green
12
358Which of the following are common to images formed by both Concave and Convex lens?
A. Real and Inverted
B. Real and Erectedd
c. virtual and Erected
D. Virtual and Real
12
359A concave mirror cannot be used as a:
A. torch reflector
B. dentist’s mirror
c. rear view mirror
D. magnifying mirror
12
360An object (O) is placed in a medium M
of refractive index ( 5 / 3 ). A convex lens of
focal length ( 15 mathrm{cm} ) is placed in front of the object as shown in the figure. Determine the position of the image
formed by the lens.
( A cdot 15 mathrm{cm} )
B. 20 cm
c. 30 ( mathrm{cm} )
D. ( 60 mathrm{cm} )
12
361What are the two possible reasons that cause this defect?12
362A ray of light travelling in air falls on the surface of a rectangular slab of a plastic material whose refractive index is ( 1.6 . ) If the incident ray makes an angle of ( 53^{circ} ) with the normal ( left(sin 53^{circ}=4 / 5right) )
find the angle made by the refracted ray with the normal.
12
363Which of the following statements is
true?
A. The angle of incidence is twice the angle of reflection
B. Angle of incidence + Glancing angle of incidence ( =90^{circ} )
C. Some types of virtual images can be caught on the screens.
D. A convex mirror forms real image
12
364Braille system are based on:
A. tasting
B. hearing
c. touching
D. smelling
12
365If an equiconvex lens is cut into two
halves along (i) ( X O X^{prime} ) and (ii) ( Y O Y^{prime} )
as shown in the figure. Let ( f, f^{prime}, f^{prime prime} ) be the focal lengths of complete lens of each, in case (i) and of each half in case
(ii) respectively.
Choose the correct statement from the
following?
( mathbf{A} cdot f^{prime}=f, f^{prime prime}=f )
B . ( f^{prime}=2 f, f^{prime prime}=2 f )
C. ( f^{prime}=f, f^{prime prime}=2 f )
D. ( f^{prime}=2 f, f^{prime prime}=f )
12
366Arrange the following combinations in the increasing order of focal length:
a) Two plano convex lenses of focal lengths ( 20 mathrm{cm} ) and ( 30 mathrm{cm} ) in contact.
b) Two convex lens of focal lengths 20 ( mathrm{cm} ) and ( 10 mathrm{cm} ) in contact.
c) Two convex lenses of focal length 25
( mathrm{cm} ) separated by ( 5 mathrm{cm} )
( A cdot a, b, c )
B. b, a, c
( c cdot a, c, b )
D. ( c, a, b )
12
367When light splits after passing through a glass prism into seven colours, the phenomenon is called:
A. reflection of light
B. refraction of light
c. dispersion of light
D. specturm
12
368A square card of side length ( 1 mathrm{mm} ) is being seen through a magnifying lens of focal length ( 10 mathrm{cm} . ) The card is placed at a distance of ( 9 mathrm{cm} ) from the lens. The apparent area of the card through the lens is
( mathbf{A} cdot 1 mathrm{cm}^{2} )
B. ( 0.81 mathrm{cm}^{2} )
c. ( 0.27 mathrm{cm}^{2} )
D. ( 0.60 mathrm{cm}^{2} )
12
369A convex lens is given, for which the minimum distance between an object
and its rel image is ( 40 mathrm{cm} . ) An object is
placed at a distance of ( 15 mathrm{cm} ) from this lens. The liner magnification of adjustment will be
A ( cdot frac{5}{3} )
B. – 2
( c cdot 2 )
D.
12
370When light travels from optically denser medium to optically rarer medium after refraction
A. ( mm<r )
в. ( m<i<m<r )
( mathbf{c} cdot m<i=m<r )
( mathbf{D} cdot m<i geq m<r )
12
371A person with a normal near point (25 ( mathrm{cm} ) ) using a compound microscope with objective of focal length ( 8.0 mathrm{mm} ) and an eyepiece of focal length ( 2.5 mathrm{cm} )
can bring an object placed at ( 9.0 mathrm{mm} )
from the objective in sharp focus. What is the separation between the two lenses? Calculate the magnifying power of the microscope.
12
372What do you mean by ‘Reflection of light’? State the laws of reflection.12
373The film of camera is compared to which part of human eye?
A. Lens
B. Retina
c. Iriss
D. choroid
12
374The focal length of a concave mirror is ( 50 mathrm{cm} ) where an object is to be placed so that its image is two times magnified, real and inverted:
A. ( 75 mathrm{cm} )
B. 72 cm
( c cdot 63 mathrm{cm} )
D. 50 cm
12
375Secondary rainblow in the atmosphere
¡s:
A. the result of polarization and dispersion of light
B. brighter than the primary rainbow
C. due to the phenomenon of double refraction
D. formed with red colour on the top
E. formed due to two reflections in the rain drop
12
376A ( 1 mathrm{cm} ) height needle is placed at a
distance of ( 0.1 ~ m ) from a convex mirror
of focal length 0.05 m, then size of the
image is
A. ( 1 mathrm{cm} )
в. ( 0.66 mathrm{cm} )
( mathrm{c} .0 .33 mathrm{cm} )
D. ( 0.5 mathrm{cm} )
12
377The angle of incidence on a plane mirror
is ( 45^{circ}, ) then the angle of reflection will
be
A . 35
B . 45
( mathrm{c} cdot 135^{circ} )
D. 145
12
378A man of height ( 170 mathrm{cm} ) wants to see his complete image in a plane mirror (while standing). His eyes are at a height of ( 160 mathrm{cm} ) from the ground.
A. minimum length of the mirror ( =80 mathrm{cm} )
B. minimum length of the mirror = 85 cm
c. bottom of the mirror should be at a height 80 cm or
more
D. bottom of the mirror should be at a height ( 85 mathrm{cm} )
12
379Why are red coloured lights are used in traffic signals to stop the vehicles?
A. minimum wavelength and less scatter.
B. maximum wavelength and more scatter.
c. maximum wavelength and less scatter.
D. less wavelength and less scatter.
12
380In a glass prism, spectrum is produced
due to :
A. refraction
B. dispersion
c. scattering
D. diffraction
12
381A man uses a concave mirror for
shaving. He keeps his face at a distance of ( 25 mathrm{cm} ) from the mirror and gets an
image which is 1.4 times enlarged. Find the focal length of the mirror.
12
382A ray of light suffers refraction through equilateral prism. The deviation produced by the prism does not depend on the :
A. angle of incidence
B. colour of light.
c. material of prism.
D. size of prism
12
383are drawn on light rays to show the direction in which light travels.
A. RAYS
B. ARROWS
c. LINES
D. LINE SEGMENTS
12
384In the creation of rainbow, the process
occurs in which of the following order?
A. reflection, refraction, dispersion and total internal reflection
B. refraction, reflection, dispersion and total internal reflection
C. dispersion, refraction, reflection and total internal reflection
D. total internal reflection, refraction, dispersion and reflection
12
385What is an object, that reflects some
light and transmits some light, called?
A . Coloured
в. ०раяче
c. Diffuse
D. Translucent
12
386A convex lens is used to form an image
of an object on a screen, If the upper half of the lens is blackened so that it
becomes opaque.Then:
A. Only half of the image will be visible
B. The image position shifts towards the lens
c. The image position shifts away from the lens
D. The brightness of the image reduces
12
387The value of numerical aperature of the objective lens of a microscope is ( 1.25 . ) If light of wavelength ( 5000 dot{A} ) is used, the minimum separation between two points, to be seen as distinct, will be :
A ( .0 .24 mu m )
в. ( 0.48 mu m )
c. ( 0.12 mu ) m
D. ( 0.38 mu m )
12
388A ray of light is normally incident on one face of an equilateral glass prism. Will the light ray suffer minimum deviation
by the prism?
A . True
B. False
12
389Looming’ in polar region
( A cdot ) Is an optical illusion
B. Arise due to the veriation of refractive index of atmosphere
C. Is an example of total internal reflection
D. All of the above
12
39013. A thin glass (refractive index 1.5) lens has optical power
of -5 D in air. Its optical power in a liquid medium is
(a) 10
(b) -25 D
(c) 25 D
(d) -1D (AIEEE 2005)
12
391A spectrum is obtained by sending a beam of white light through a prism. ( mathbf{A} )
second prism exactly similar to the first
one is placed in an inverted position
with the sides parallel to the first. Now
A. A new spectrum will be formed on the screen with double the number of colours present in the previous spectrum
B. New spectrum will be obtained on the screen with only half the number of colours present in the previous spectrum
C. Previous spectrum will disappear and we will obtain a white light formed by the fusion of the colours
D. A spectrum with same number of colours present in the previous spectrum will be formed but their wave lengths will be increased twice
12
392A concave lens forms the image of an
object such that the distance between
the object and image is ( 10 mathrm{cm} ) and the
magnification produced is ( 1 / 4 . ) The focal length of the lens will be
( mathbf{A} cdot 8.6 mathrm{cm} )
B. ( 6.2 mathrm{cm} )
c. ( 10 mathrm{cm} )
D. ( 4.4 mathrm{cm} )
12
393Which of the following phenomena contributes significantly to the reddish appearance of the sun at sunrise or
sunset?
A. Dispersion of light
B. Scattering of light
c. Total internal reflection of light
D. Reflection of light from the earth
12
394When an equilateral glass prism is in minimum deviation position,
(A) the refracted ray is parallel to the base of the prism
(B) the angle of incidence is equal to the
angle of emergence. Choose the correct option.
A. Only A is true
B. Only B is true
c. Both A and B are true
D. Both A and B are false
12
395The power of a lens is -5 D. Find its focal
length.
12
396(a) State Snell’s law for refraction of
light.
(b) A concave mirror forms two times
magnified and real image of an object
placed at ( 15 mathrm{cm} ) from its pole. Determine the distance of image from mirror and focal length of the mirror.
12
397Three observers ( A, B ) and ( C ) measure
the speed of light coming from a source
to be ( boldsymbol{v}_{A}, boldsymbol{v}_{B} ) and ( boldsymbol{v}_{C} . ) The observer ( boldsymbol{A} )
moves towards the source and ( C ) moves
away from the source at the same
speed. The observer ( boldsymbol{B} ) stays stationary. The surrounding space is vacuum
everywhere.
This question has multiple correct options
( mathbf{A} cdot v_{A}>v_{B}>v_{C} )
В . ( v_{A}<v_{B}<v_{C} )
( mathbf{c} cdot v_{A}=v_{B}=v_{C} )
D. ( v_{B}=frac{1}{2}left(v_{A}+v_{C}right) )
12
398A microscope in which maximum magnification is achieved, but the object cannot be seen by eye is called
A. simple microscope
B. Dissecting microscope
c. Electron microscope
D. Phase contrast microscope
E. Compound microscope
12
399image of an object approching a convex mirror of radius of curvature ( 20 mathrm{m} ) along its optical axis so is observed to move from ( frac{25}{3} m ) to ( frac{50}{7} m ) into 30 s. what is the speed of the object in ( K m / h ? )
A . 3
B. 4
( c .5 )
D. 6
12
400Fill in the blank with appropriate
answer:

A compound microscope is used because a realistic simple microscope
does not have
magnification.

12
401What are the colours of the Sun
observed most during sunrise/sunset and noon?
A. white and red
B. reddish and orange
c. yellow and reddish
D. orange and blue
12
402An equiconvex lens is made from glass of refractive index ( 1.5 . ) If the radius of
each surface is changed from 5 ( mathrm{cm} ) to
( 6 c m, ) then the power:
A. Remains unchanged
B. Increases by 3.33 D
c. Decreases by 3.33 D
D. Decreases by ( 5.5 D )
12
403If an object of ( 10 mathrm{cm} ) height is placed at
a distance of ( 36 mathrm{cm} ) from a concave
mirror of focal length ( 12 mathrm{cm} ), find the
position, nature and height of image.
12
404A compound microscope has a magnification 30. The focal length of eyepiece is ( 5 mathrm{cm} . ) Assuming that the final image is formed at least distance of distinct vision ( (25 mathrm{cm}) ). Find the
magnification produced by objective.
12
405In hypermetropia, the image of near object is formed:
A. Before the retina
B. On retina
c. Behind the retina
D. Above the retina
12
406A point source of light at the surface of a sphere causes a parallel beam of light to emerge from the opposite surface of the sphere. The refractive index of the material of the sphere is?
A . 5
В. ( 5 / 3 )
c. 2
D. 2.5
12
407An unnumbered wall clock shows time
( 04: 25: 37, ) where ist term represents
hours, 2nd represents minutes and the last term represents seconds. What time will its image in a plane mirror show
( mathbf{A} cdot 08: 35: 23 )
B. ( 0 .: 35: 23 )
c. 07: 35: 23
D. none of these
12
408The spreading of white light into its component colours is known as.
A. Dispersion
B. Deviation
c. Refraction
D. Diffraction
12
409In the image formed by a plane mirror, the left of the object appears on the right and the right appears on the left. This is called lateral inversion.
A . True
B. False
12
410If the focal lengths of objective and eyelens of a microscope are ( 1.2 mathrm{cm} ) and ( 3 mathrm{cm} ) respectively and the object is put ( 1.25 mathrm{cm} ) away from the objective lens and the final image is formed at infinity, then magnifying power of the microscope is
A . 150
B. 200
c. 250
D. 400
12
411An object is placed in front of a thin convex lens of focal length ( 30 mathrm{cm} ) and a plane mirror is placed ( 15 mathrm{cm} ) behind the lens. If the final image of the object coincides with the object, the distance of the object from the lens is :
( A cdot 60 mathrm{cm} )
B. 30 cm
c. ( 15 mathrm{cm} )
D. 25 cm
12
412The objective and eyepiece of an astronomical telescope are doubled convex lenses with refractive index 1.5
When the telescope is adjusted to infinity, the separation between the two lenses is ( 16 mathrm{cm} ). If the space between
the lenses is now filled with water and again telescope is adjusted for infinity, then the present separation between the lenses is:
A. ( 8 mathrm{cm} )
в. 16 ст
( c cdot 24 c m )
D. 32 ст
12
413Assertion
The refractive index of a prism depends only on the kind of glass of which it is made of and the colour of light.
Reason
The refractive index of a prism depends on the refracting angle of the prism and the angle of minimum deviation.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
414Some stars appear red in colour and
some blue in colour. Which one of the
statements is true?
A. Star with blue colour has more temperature than red colour star
B. Temperature of blue colour star is less than red colour star
c. There is no relation between colour of the star and temperature
D. Blue colour star and red colour star has equal temperature
12
41521. An object 2.4 m in front of a lens forms a sharp image on
a film 12 cm behind the lens. A glass plate 1 cm thick,
of refractive index 1.50, is interposed between lens and
film with its plane faces parallel to film. At what distance
(from lens) should object shifted to be in sharp focus on
film?
(a) 7.2 m
(b) 2.4 m
(c) 3.2 m
(d) 5.6 m (AIEEE 2012)
12
416Mark the INCORRECT statement:
A. Light travels along a straight line
B. A mirror does not change the medium of light falling on it
C. Things are only visible when light from our eyes reaches the object
D. All visible things either reflect or emit light
12
417Which colour deviate minimum during the dispersion of light through a prism?12
418A ray of light falls on the surface of a spherical glass paperweight making an angle ( a ) with the normal and is refracted
in the medium at angle ( b ). The angle of deviation of the emergent ray from the
direction of incident ray is :
A ( . a-b )
в. ( 2(a-b) )
c. ( frac{(a-b)}{2} )
D. ( b-a )
12
419The phenomenon by which the incident light falling on a surface is sent back into the same medium is known as
A. Reflection
B. Refraction
c. Dispersion
D. None
12
420A card sheet divided into squares each
of size ( 1 mathrm{mm}^{2} ) is being viewed at a distance of ( 9 mathrm{cm} ) through a magnifying glass (a converging lens of focal length ( 9 mathrm{cm} ) ) held close to the eye.(a) What is the magnification produced by the lens? How much is the area of each
square in the virtual image?(b) What is the angular magnification (magnifying power) of the lens?(c) Is the magnification in
(a) equal to the magnifying power in (b)? Explain
12
421When a ray of light strikes a plane mirror along the normal, the angle of incidence is –
A . ( 90^{circ} )
B. zero
( c cdot 45 )
D. none of these
12
422Concave lens is used to correct
A. Myopia
B. Presbiopia
C. Hypermetropia
D. cataract
12
423Which of the following statements are
true?
a. The spectrum of sunlight has 7 colors
b. Spectrum is seen due to bending of lights of different colors at different
angles with respect to the incident ray through a prism
c. Red light bends the least whereas violet light bends the maximum
d. Rainbow is an example of dispersion of light
A. a, band c
B. c and d
c. a, c and d
D. All of these
12
424Rainbow is an example of dispresion of sunlight.Expalin its formation.12
425State whether the given statement is
True or False.
The front portion of the eye is filled with vitreous humour.
12
426If the radius of curvature of a spherical
mirror is ( 20 mathrm{cm}, ) then its focal length is
( mathrm{cm} )
A . 20
B. 40
c. 10
D. None of these
12
427Explain how you can take care of your
eyes.
12
428Power of a lens can’t be measured in
A. ( m )
B. ( W )
c. Horse power
D. None of these
12
429Refraction index of water is ( 4 / 3 )
Calculate speed of light in water.
A ( cdot 3 times 10^{8} m / s )
В. ( 62 m / s )
C ( .2 .25 times 10^{8} mathrm{m} / mathrm{s} )
D. 1.25
12
430Establish the formula ( frac{1}{boldsymbol{f}}=frac{1}{boldsymbol{u}}+frac{1}{boldsymbol{v}} ) for ( mathbf{a} )
concave mirror, where symbols have their usual meanings.
12
431(a) Draw a ray diagram showing the image formation by a compound microscope. Hence obtain expression for total magnification when the image is formed at infinity
(b) Distinguish between myopia and hypermetropia. Show diagrammatically how these defect can be corrected.
12
432Fill in the blanks:
Light is a form of that we
detect with our
A. energy, ears
B. corpuscles, eyes
c. energy, eyes
D. sensation, skin
12
433An achromatic combination of concave
and convex lens has power 5 D. If the power of convex lens is 4 D, then the
magnitude of focal length of concave lens is?
12
434Cilliary muscles in the eye:
A. hold the eye lens in place
B. increase or decrease focal length of eye lens.
C. both (a) and (b)
D. none of these
12
435Speed of light is maximum in:
A. glass
B. vaccumm
c. water
D. nylon
12
436The Speed of light in vacuum is:
A ( cdot 2 times 10^{10} mathrm{m} / mathrm{s} )
B . ( 3 times 10^{8} mathrm{m} / mathrm{s} )
c. ( 4 times 10^{5} mathrm{m} / mathrm{s} )
D. ( 2 times 10^{12} mathrm{m} / mathrm{s} )
12
437Match the statements in Column A, with
those in Column B.
12
438Four lenses of focal length
( +15 c m,+20 c m,+150 c m ) and
( +250 c m ) are available for making an astronomical telescope. To produce the largest magnification, the focal length of the eyepiece should be
A ( .+15 mathrm{cm} )
B. +20 cm
( mathbf{c} .+150 mathrm{cm} )
D. ( +250 c m )
12
439Figure shown a spherical concave
mirror with its pole at (0,0) and
principal axis along x axis. There is a
point object at ( (-40 mathrm{cm}, 1 mathrm{cm}), ) find the
position of image.
12
440Write the structure of eye lens and state
the role of ciliary muscle in the human
eye
12
441A ray of light is normally incident on one face of an equilateral glass prism. What is the angle of refraction from the
first face of the prism?
A ( .90^{circ} )
B . ( 45^{circ} )
( c cdot 30^{circ} )
D. ( 0^{circ} )
12
442State the cause of dispersion of white light by a glass prism. How did Newton, using two identical glass prisms, show that white light is made of seven colors? Draw a ray diagram to show the path of a narrow beam of white light, through a combination of two identical primes arranged together in inverted position with respect to each other, when it is allowed to fall obliquely on one of the
faces of the first prism of the combination.
12
443The edge formed by the two refracting surfaces is the refracting edge in glass prism. Is this statement True or False?
A. True
B. False
12
444The curvature of the eye lens can be
modified by
A. ciliary muscles
B. iriss
c. pupil
D. cornea
12
445Formation of real image using a biconvex lens is shown below:
f the whole set up is immersed in water
without disturbing the object and the screen position, what will one observe
on the screen?
A. Image disappears
B. No change
C. Erect real image
D. Magnified image
12
446A parallel narrow beam of light is
incident on the surface of a transparent
hemisphere of radius ( boldsymbol{R} ) and refractive
index ( mu=1.5 . ) The position of the image
formed by refraction at the spherical
surface only is
A. ( R / 2 )
B. ( 3 R )
( c . R / 3 )
( mathbf{D} cdot 2 R )
12
447With the help of a diagram explain the
formation of rainbow in the sky. List two
essential conditions for observing a rainbow
12
448The absolute refractive index of glass
and water are ( 3 / 2 ) and ( 4 / 3, ) respectively. If the speed of light in glass is ( 2 times 10^{8} )
( mathrm{m} / mathrm{s}, ) calculate the speed of light in :
(a) vacuum
(b) water
12
449The constant ratio of the sine of angle of incidence to the sine of angle of refraction is also known as:
A. Snell’s law
B. Optical density
c. Relative density
D. None of these
12
450Light of wavelength ( lambda_{1} ) enters a medium
with refractive index ( n_{2} ) from a medium
with refractive index ( n_{1} ). What is the
wavelength of light in second medium?
12
451A ray of light passes through an equilateral prism (refractive index ( = )
1.5) such that the angle of incidence is
equal to the angle of emergence and the latter is equal to ( 3 / 4 ) th the angle of the prism. The angle of deviation is:
A ( .20^{circ} )
B. ( 39^{circ} )
c. ( 5^{circ} )
D. ( 30^{circ} )
12
452A spherical convex surface of radius of
curvature ( R ) separates ( operatorname{air}left(mu_{a}=1right) ) from
( operatorname{glass}left(a mu_{g}=1.5right) . ) The centre of
curvature is in the glass. A point object P placed in air is found to have a real image ( Q ) in the glass. The line PQ cuts the surface at a point 0 and ( P 0=0 Q ) The distance PO is equal to
A. 5R
B. 3R
( c cdot 2 R )
D. 1.5 R
12
453A microscope consists of an objective with a focal length ( 2 mathrm{mm} ) and an eye piece with a focal length ( 40 mathrm{mm} ). The distance between the foci (which are between the lenses) of objective and eyepiece is ( 18 mathrm{cm} . ) The total
magnification of the microscope is (Consider normal adjustment and take ( mathrm{D}=25 mathrm{cm} )
A . 562.5
B. 625
c. 265
D. 62.5
12
454Height of the image of an principal axis produced by a convex lens is double the object height. If the focal length of the
lens is ( 20 mathrm{cm} ), then the image distance from lens is :
( mathbf{A} cdot 10 mathrm{cm} )
B. ( 30 mathrm{cm} )
( mathbf{c} cdot 40 mathrm{cm} )
D. Both (1)( &(2) )
12
455When a light ray falls on a perfectly reflective mirror at an angle. Identify which of the following statement is true about the ray?
A. The frequency of the light ray changes
B. The wavelength of the light ray changes
C. The velocity of the light ray changes
D. The period of the light ray changes
E. The direction of motion of the light ray changes
12
456What will be the effect of refraction on a
lemon, when it is placed in a glass tumbler filled with water?
A. It will appear smaller than the actual size
B. It will appear bigger than the actual size
c. It will be invisible
D. It will appear raised
12
457A ( 1.2 c m ) long pin is placed perpendicular to the principal axis of a
convex mirror of focal length ( 12 mathrm{cm}, ) at a
distance of ( 8 mathrm{cm} ) from it. Find the
location of the image. Find the height of the image.
12
458The power of a convex lens of focal length 2 metre will be:
A ( .+0.5 D )
в. ( +5 D )
( mathrm{c} cdot+50 D )
D. – 5D
12
459Riya and Priya were sitting around a round table. They noticed that they could see their own and each other’s
image onto the table top. Then table top
is made of
A. Unpolished wood, covered with white cloth
B. Polished glass of red colour
C. Glass covered with cellophane paper
D. Smoked glass covered with green colour cloth.
12
460A person cannot clearly see objects farther than ( 12 mathrm{m} ) from the eye. Name the defect in vision he is suffering from
and the lens that should be used to
correct this defect.
12
461The most effective resource for visually challenged person is
A. Telescopic aid
B. Auditory aid
c. Lenses
D. Braille system
12
462When we see an object, the image formed on the retina is
(i) real (ii) virtual(iii) erect (iv) inverted
A. (i) and (iv) only
B. (i), (ii), (iii)
c. (iv) only
D. (ii) and (iv)
12
463The lens used to correct long sightedness or hypermetropla.
A. Convex lens
B. Concave lens
c. simple lens
D. Cylindrical lens
12
464A horizontal parallel beam of light
passes through a vertical convex lens of
focal length ( 20 mathrm{cm} ) and is then reflected by a titled plane mirror so that it coverages to a point I. The distance Pl is ( 10 mathrm{cm} )
M is a point at which the axis of the lens
intersects the mirror. The distance PM
is ( 10 mathrm{cm} . ) The angle which the mirror makes with the horizontal is
( mathbf{A} cdot 15^{circ} )
B. ( 30^{circ} )
( mathbf{c} cdot 45^{circ} )
D. ( 60^{circ} )
12
465An infinitely long rod lies along the axis
of a concave mirror of focal length ( f ). The near end of the rod is at a distance ( u> )
( f ) from the mirror. Its image will have a
length :
( mathbf{A} cdot f^{2} /(u-f) )
B. ( u f /(u-f) )
c. ( f^{2} /(u+f) )
D. ( u f /(u+f) )
12
466An upright object is placed at a
distance in front of a converging lens equal to twice the focal length ( 20 mathrm{cm} ) of
the lens. On the other side there is a
concave mirror of focal length ( 15 mathrm{cm} )
separated from thelens by a distance of
70 cm. Then select the correct
statements from the following
his question has multiple correct options
A. Magnification for the system is ( 1 / 2 )
B. Magnification for the system is
c. Final image by the system will real and at distance of ( 80 mathrm{cm} ) from centre of curvature of spherical mirror
ification for the system is ( +1 / 2 )
12
467Reflection is
A. Bending of ray of light.
B. Bouncing back of ray of light.
C. Light travelling in a straight line.
D. None of these.
12
468A broader bundle of light rays is called a
A. Beam of light
B. Ray of light
c. Bundle of light
D. None of these
12
469The angle between incident ray and
normal is ( 30^{circ}, ) then the angle of
incidence will be
A ( .60^{circ} )
B. ( 30^{circ} )
( c .90^{circ} )
D. 150
12
470What happen to the image, if a convex lens is made up of two different transparent material, as shown in
figure?
12
471In an astronomical telescope the focal lengths of objective and eyepiece should respectively be :
A. large and small
B. small and large
c. equal
D. too small are too large
12
472Differentiate between regular and
diffused reflection. Does diffused
reflection mean the failure of the laws of
reflection?
12
473A glass prism of refractive index 1.5 is immersed in water of refractive index
4/3. A light ray incident normally on
face ( A B ) is totally reflected at face ( A C ) if
( mathbf{A} cdot sin theta>8 / 9 )
B. ( sin theta<2 / 3 )
( c cdot sin theta=sqrt{3} / 2 )
D. ( 2 / 3<sin theta leq 8 / 9 )
12
474A candle flame ( 3 mathrm{cm} ) high is placed at a distance of ( 3 mathrm{m} ) from a wall.how far from
the wall must a concave mirror be
placed so that it may form ( 9 mathrm{cm} ) high image of the flame on the same wall? Also find the focal length of the mirror.
12
475A beam of white light traveling in medium ( A ) strikes the interface to
another transparent medium, medium
B. If the speed of white light is less in
medium ( B ) than in medium ( A ), the
beam will
A. refract toward the normal
B. refract away from the normal
c. undergo total internal reflection
D. have an angle of reflection smaller than the angle of incidence
E. have an angle of reflection greater than the angle of incidence
12
47642. You are given two identical plano-
convex lenses. When you place an
object 20 cm to the left of a single
plano-convex lens, the image appears
40 cm to the right of the lens. You
then arrange the two plano-convex
Plano-
Double
lenses back to back to form a double
convex
convex
convex lens. If the object is 20 cm to
the left of this new lens, what is the approximate location
of the image?
(a) 10 cm to the right of the lens
(b) 20 cm to the right of the lens
(c) 80 cm to the right of the lens
(d) 80 cm to the left of the lens
12
477A ( 4 mathrm{cm} ) tall object is placed perpendicular to the principal axis of a convex lens of focal length ( 24 mathrm{cm} . ) The distance of the object from the lens is 16 cm. Find the position, size and nature of the image formed, using the lens formula.12
478A ray of light is incident on a glass slab
of refractive index ( 1.52 . ) if the reflected
and refracted rays of light are mutually perpendicular to each other then the angle of incidence will be
A ( .90^{circ} )
B . ( 60^{circ} )
c. ( 56^{circ} ) 40
D cdot ( 19^{circ} 58^{prime} )
12
479A magnifying glass is used to read the newspaper. As it is moved far away from
the newspaper
A. Text becomes blurred and magnification reduces
B. Text becomes more focussed and magnification reduces
c. Text becomes more focused and magnification increases
D. Text becomes blurred and magnification increases
12
480What is the refractive index of a prism
whose angle ( A=60^{circ} ) and angle of
minimum deviation ( boldsymbol{d}_{m}=mathbf{8 0}^{o} ? )
A ( cdot sqrt{2} )
B. ( sin ^{-1}(sqrt{3}) )
( mathbf{c} cdot tan ^{-1}(sqrt{2}) )
D. ( tan ^{-1}(sqrt{3}) )
12
48113. To find index error for u, when a knitting needle of length
20.0 cm is adjusted between pole and object needle, the
separation between the indices of object needle and mirror
was observed to be 20.2 cm. Index correction for u is
(a) -0.2 cm
(b) 0.2 cm
(c) -0.1 cm
(d) 0.1 cm
Sal (hl Indey error (Y ordina
12
482An ideal mirror:
A. Absorbs all the amount of light incident on it
B. Refracts all the light
C. Reflects all the light
D. None of the above
12
483The focal length of a convex lens is ( 25 mathrm{cm} . ) Find its power with sign.
( A cdot+4 D )
в. ( -4 D )
( c .+2.5 D )
D. ( -2.5 D )
12
484Which of the following is Snell’s law?
A ( cdot n_{1} sin i=frac{sin r}{n_{2}} )
B. ( frac{n_{1}}{n_{2}}=frac{sin r}{sin i} )
c. ( frac{n_{2}}{n_{1}}=frac{sin r}{sin i} )
D. ( n_{2} sin i= ) constant
12
485Blue colour of sky is due to:
A. scattering.
B. absorption.
c. reflection.
D. refraction.
12
486In secondary rainbow what is the order of colours observed from earth?
A. Violet innermost, Red outermost
B. Red innermost, Violet outermost
c. Random
D. White and dark alternatively
12
487Derive the relationship between the
focal length and radius of curvature of
spherical mirror.
12
488(a) A mobile phone lies along the principal axis of a concave mirror. Show, with the help of a suitable
diagram, the formation of its image. Explain why magnification is not uniform.
(b) Suppose the lower half of the concave mirror’s reflecting surface is
covered with an opaque material. What
effect this will have on the image of the object? Explain.
12
489A convex mirror used for rear view on an
automobile has a radius of curvature of
( 3.00 mathrm{m} . ) If a bus is located at ( 5.00 mathrm{m} ) from
this mirror, find magnification?
( A cdot+0.23 )
B. – -0.23
( c cdot+0.45 )
D. -0.45
12
490A mark on the surface of a glass sphere( ( boldsymbol{mu}=1.5) ) is viewed from a diametrically opposite position. It appears to be at a distance ( 10 mathrm{cm} ) from its actual position. The radius of sphere is:
A. ( 5 mathrm{cm} )
B. 10 ( mathrm{cm} )
c. ( 15 mathrm{cm} )
D. 20 cm
12
491An object is placed in front of a spherical mirror whose 2 times magnified images is formed on the screen. Then choose the
CORRECT option:
A. Mirror is concave ( mathrm{m}=+2 )
B. Mirror is concave ( m=-2 )
c. Mirror is convex ( mathrm{m}=+2 )
D. Mirror is convex ( mathrm{m}=-2 )
12
492When a ray of light is incident normally on one refracting surface of an equilateral prism (Refractive index of the material of the prism ( =1.5 ) )
A . emerging ray is deviated by ( 30^{circ} )
B. emerging ray is deviated by 45
c. emerging ray just grazes the second refracting surface
D. The ray undergoes total internal reflection at the second refracting surface
12
493When the light is very bright, then:
A. Iris makes pupil expand
B. Iris makes pupil contract
C. Iris and pupil remain as they are
D. None of these
12
494Which of the following statements is correct regarding the propagation of light of different colors of white light in air?
A. Red light moves fastest
B. Blue light moves faster than green light
c. All the colours of the white light move with the same speed
D. Yellow light moves with the mean speed as that of the red and the violet light
12
495An object of ( 2 mathrm{cm} ) height is placed at a distance of ( 16 mathrm{cm} ) from a concave mirror
which produces a real image ( -3 c m ) height. What is the focal length ( & ) position of the image?
12
496The image which can not be taken on the screen is called
A. a real image
B. a virtual image
c. either a real or a virtual image
D. neither a real nor a virtual image
12
497A ray of light takes grazing incidence on the first face of a prism and the
emergent ray is normal to the ( 2^{n d} ) face
of the prism. If ( mathrm{D} ) is angle of deviation then the refracting angle of the prism is equal to
A ( cdot 90^{circ}-2 D )
B. ( 90^{circ}-D )
c. ( 90^{circ}-frac{D}{2} )
D. ( 180^{circ}-2 D )
12
498Who amongst the following used corpuscular theory to explain reflection and refraction of light?
A. Newton
B. Maxwell
c. Young
D. Hertz
12
499occurs when a light ray bounces back from a barrier.
A. Refraction
B. Reflection
c. Dispersion
D. Scattering
12
500Far point of a person is ( 5 m . ) In order that he has normal vision what kind of
spectacles should be use
A. Concave lens with focal length ( 5 m )
B. Concave lens with focal length ( 10 mathrm{m} )
c. convex lens with focal length ( 5 m )
D. Convex lens with focal length ( -2.5 mathrm{m} )
12
501The word ‘VIBGYOR’ is made of the
initial letters of the seven colours of the
A. Prism
B. Red light
c. shadow
D. Rainbow
12
502A ray of light is incident normally on one refracting surface of an equilateral
prism. If the refractive index of the
material of the prism is ( 1.5, ) then:
A. the emergent ray is deviated by ( 30^{circ} )
B. the emergent ray is deviated by ( 60^{circ} )
C. the emergent ray just graces the second reflecting surface
D. the ray undergoes total internal reflection at second refracting surface
E. the ray emerges normally from the second refracting surface
12
503Copy the diagram given below and
complete the path of light ray till it
emerges out of the prism. The critical
angle of glass is ( 42^{circ} . ) In your diagram
mark the angles wherever necessary.
12
5046. The graph shows variation of
v with change in u for a mirror.
Points plotted above the point P
on the curve are for values of v
(a) Smaller than /
(b) Smaller than 21
(c) Larger than 21
(d) Larger than
12
505Why are danger signals always red in color?
A. Red light is least scattered by fog and smoke
B. It is the color of danger
c. Both A and B
D. None of these
12
506A concave mirror forms the image of an
object on a screen. If the lower half of
the mirror is covered with an opaque
card, the effect would be to make the
A. image less bright.
B. lower half of the image disappear.
c. upper half of the image disappear.
D. image blurred.
12
507Distinguish between:
Convex mirror and concave mirror
12
508In a compound microscope the intermediate image is :
A. real, inverted & magnified
B. real, erect & magnifiedd
c. virtual, erect & magnified
D. virtual, erect & reduced
12
509A compound microscope has on objective of focal length ( 0.5 mathrm{cm} ) and a tube length of ( 15 mathrm{cm} . ) If it produces and angular magnification of 225 in normal adjustment, find the focal length of the
eyepiece.
A. ( 3.33 mathrm{cm} )
B. ( 15 mathrm{cm} )
c. ( 2.25 mathrm{cm} )
D. 3.5 cm
12
510Name one property of waves that do not
change when the wave passes from one medium to another
12
511Microscopes are used for magnification:
A. True
B. False
12
512In the case of plane mirror. from the
mirror distance of the image ( = ) distance of the
A. Second image
B. object
c. both
D. none
12
513Two thin similar convex glass pieces are joined together front to front, with its rear portion silvered such that a sharp image is formed 0.2 ( mathrm{m} ) for an object at infinity. When the air between the glass pieces is replaced by water ( left(mu=frac{4}{3}right), ) find the position of image.12
514left of a thin convex lens of focal length
( 30 mathrm{cm} . ) A convex spherical mirror of
radius of curvature ( 100 mathrm{cm} ) is placed to
the right of the lens at a distance of
( 50 mathrm{cm} . ) The mirror is titled such that the
axis of the mirror is at a angle ( boldsymbol{theta}=mathbf{3 0}^{circ} )
to the axis of the lens, as shown in the
figure.

If the origin of the coordinate system is
taken to be at the centre of the lens, the
coordinates ( (text { in } c m) ) of the point ( (x, y) )
at which the image is formed are:
( mathbf{A} cdot(125 / 3,25 / sqrt{3}) )
B ( cdot(50-25 sqrt{3}, 25) )
c. (0,0)
D. ( (25,25 sqrt{3}) )

12
515A reflecting surface is curved outwards. The mirror formed will be :
A. Concave
B. Plane
c. convex
D. None of these
12
516Myopia of the common defects of vision and the type of lens used to remove it.12
517The focal length of a symmetric biconvex lens is ( 20 mathrm{cm} ). If the refractive
index of the material of the prism is 1.5
the radius of curvature of one of two
surfaces is
( A cdot 10 mathrm{cm} )
B. 20 cm
c. ( 40 mathrm{cm} )
D. 80 cm
12
518Assertion
A beam of light rays has been reflected
from a rough surface.
Reason
Amplitude of incident and reflected rays
would be different.
A. Both Assertion and Reason are correct and Reason is
the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
519Red and blue beams of light is incident
on a prism as shown in the figure.
Which of the following statements is
true?
A. The blue light bends more than the red light as the blue light has a longer wavelength.
B. The red light bends more than the blue light as the red light has a longer wavelength.
C. The blue light bends more than the red light as the blue light has a shorter wavelength.
D. The red light bends more than the blue light as the red light has a shorter wavelength.
E. The red and blue lights bend by the same amount as all colors of light refract equally.
12
520A biconvex lens has focal length of 25
cm. the radius of curvature of one the
surface is double of the other. Find the
radii. given ( mu_{l e n s}=1.5 )
A. ( 37.5 mathrm{cm}, 75 mathrm{cm} )
B. ( 18.75 mathrm{cm}, 37.5 mathrm{cm} )
( c .7 .5 mathrm{cm}, 15 mathrm{cm} )
D. ( 15 mathrm{cm}, 30 mathrm{cm} )
12
521A compound microscope has an objective of focal length ( 2 mathrm{cm} ) and an eye-piece of focal length ( 6.25 mathrm{cm}, ) which are separated by 15 cm.fr the final image is formed at the least distance of distinct vision ( 25 mathrm{cm}, ) distance to the object from the objective is
A. ( 20 mathrm{cm} )
B. 8.75 cm
( c .1 .50 mathrm{cm} )
D. 2.5 ( mathrm{cm} )
12
522State whether given statement is True or False

During refraction through prism a ray bends away from its base.
A. True
B. False

12
523Mark the statement which is true for
diffused reflection:
A. Diffused reflection is due to failure of laws of reflection
B. It is caused due to irregularities in the reflecting surface
c. When the incident light is diffused in nature it causes diffused reflection
D. All are true
12
524Which type of mirror is used by a dentist?
A . Plane
B. convex
c. concave
D. Both (b) and (c)
12
525Study the following diagram carefully
and then answer the questions that follow. The diagram is depicting a
defect of the human eye.
(i) Identify the defect shown in the
diagram.
(ii) Give two possible reasons for the
above defect.
(iii) Draw a neat labelled diagram to
show how the above defect can be
rectified.
12
526A point object ( boldsymbol{O} ) is placed at a distance
of ( 0.3 m ) from a convex lens (focal
length ( 0.2 m ) ) cut into two halves each
of which is displaced by ( 0.0005 m ) as
shown in the figure.
f this arrangement will generate more
than one image, then what will be the
total number of images?
4
B.
( c )
D
12
527A light ray is travelling between two media as given below. The angle of incidence on the boundary in all the
cases is ( 30^{circ} . ) Identify the sequence of increasing order of angles of refraction.
a) Air to water
b) Water to glass
c) Glass to water
( A cdot a, b, c )
B. b, c, a
( c cdot c, a, b )
D. a, c, b
12
528A light bulb burns in front of the center
of a ( 40 mathrm{cm} ) wide plane mirror that is hung vertically on a wall. A man walks
in front of the mirror along a line that is parallel to the mirror and twice as far from it as the bulb. The greatest
distance he can walk and still see the
image of the bulb.
( mathbf{A} cdot 20 mathrm{cm} )
B. ( 40 mathrm{cm} )
c. ( 60 mathrm{cm} )
D. ( 120 mathrm{cm} )
12
529An object of ( 2 mathrm{cm} ) height is placed at a
distance of ( 10 mathrm{cm} ) from a concave mirror
of radius of curvature ( 30 mathrm{cm} . ) Find the image distance, height and magnification.
12
530A myopic person cannot see clearly:
A. near objects
B. objects placed at the least distance of distinct vision
C. very far objects
D. none
12
531In the adjoining diagram,a wavelength
AB, moving in air is incident on a plane
glass surface XY. Its position CD after
refraction through a glass slab is shown also along with the normals drawn at ( A )
and D. The refractive index of glass with
respect to air ( (mu=1) ) will be equal to
A. ( frac{sin theta}{sin theta^{prime}} )
B. ( frac{sin theta}{sin phi^{prime}} )
c. ( frac{sin phi^{prime}}{sin theta} )
( D )
12
532A person needs a lens of power -4.5 D for correction of her vision. What is the
focal length of the corrective lens?
A. ( f=-0.25 mathrm{m} )
B. ( f=+0.22 mathrm{m} )
c. ( f=1.22 mathrm{m} )
D. ( f=-0.22 mathrm{m} )
12
533Which of the following phenomena is related to the formation of rainbows?
This question has multiple correct options
A . Reflection
B. Refraction
c. Dispersion
D. Scattering
12
534Which of the following statements is
correct concerning the passage of white light into a glass prism?
A. All the colours of white light travel with the same speed
B. The violet colour travels slower than the red colour
C. The violet colour travels faster than the red colour
D. Greater the wavelength, slower the speed of colour
12
535If two mirrors are inclined at some
angle ( theta . ) An object is placed between the mirrors and there are 5 images formed
for an object, then ( theta ) is may be
A ( cdot 45^{circ} )
B. ( 53^{circ} )
( c cdot 63^{circ} )
D. ( 75^{circ} )
12
536Fill in the blank:
When the angle of incidence increases, glancing angle of reflection
A. increases
B. remains same
c. decreases
D. becomes infinite
12
537The radius of curvature for a plane mirror is
A. Positive
B. Negative
c. Infinite
D. None of these
12
538Choose the correct options.
Having two eyes facilitates in:
A. Increasing the field of view
B. Giving 3 dimensional view
C. Developing the concept of distance / size.
A. A only
B. A and B only
c. B only
D. ( A, B ) and ( C )
12
539Figure shows the ray diagram of a
A. Simple microscope
B. Compound microscope
c. simple Telescope
Compound Telescope
12
540An air bubble in water shines because
of the phenomenon of:
A. reflection
B. refraction
c. diffraction
D. total internal reflection
12
541If parabolic profile is used for refractive index in the core, what is the name
given to such core?
A. single mode core
B. multi mode core
c. differential mode core
D. curvilinear differential core
12
54244. Consider an equiconvex lens of radius of curvature R and
focal length f. Iff>R, the refractive index ju of the material
of the lens
(a) is greater than zero but less than 1.5
(b) is greater than 1.5 but less than 2.0
(c) is greater than 1.0 but less than 1.5
(d) none of these
11
12
543What will be the radius of curvature of a
concave mirror whose focal length is 25
( mathrm{cm} ? )
12
544Three right angled prisms of refractive
indices ( mu_{1}, mu_{2} ) and ( mu_{3} ) are joined
together ao that the faces of the middle
prism are each in contact with one of
the outside prisms. If the ray passes through the composite block undeviated, then
A ( cdot 1+mu_{2}^{2}=mu_{1}^{2}+mu_{3}^{2} )
B ( cdot mu_{1}^{2}-mu_{3}^{2}+mu_{2}^{3}=1 )
C. ( mu_{1}^{2}-mu_{3}^{2}-mu_{2}^{3}=1 )
D ( cdot mu_{2}^{2}+mu_{3}^{3}-mu_{2}^{1}=1 )
12
545A ray of light is incident on a glass slab
making an angle of ( 60^{0} ) with the surface. Calculate the angle of
refraction in glass and the velocity of light in glass if the refractive index of glass and the velocity of light in air are 1.5 and ( 3.0 times 10^{8} mathrm{m} / mathrm{s} ) respectively.
A ( cdot 28^{circ} 30^{prime}, 3 times 10^{8} mathrm{ms}^{-1} )
B . ( 40^{circ} 20^{prime}, 2.5 times 10^{8} mathrm{ms}^{-1} )
C. ( 35^{circ} 15^{prime}, 2 times 10^{8} mathrm{ms}^{-1} )
D. ( 28^{circ} 30^{prime}, 2.5 times 10^{8} mathrm{ms}^{-1} )
12
54634. Refraction takes place at a convex spherical boundary
separating glass-air medium. For the image to be real,
the object distance (u= 3/2) should be/is
(a) greater than three times the radius of curvature of
the refracting surface
(b) greater than two times the radius of curvature of the
refracting surface
(c) greater than the radius of curvature of the refracting
surface
(d) independent of the radius of curvature of the
refracting surface
12
547In an equilateral glass prism, for two
angles of incidence, differing by ( 10^{circ}, ) the
angle of deviation is found to be ( 40^{circ} ) find these angles of incidence.
12
548In the figure shown, A ray of light is
falling at the angle of incidence ( boldsymbol{theta} )
Identify which of the following best
describe the angle of reflection?
( A )
B. 2
( c cdot 3 )
D. 4
( E cdot 5 )
12
549A ray of light ( O P ) passes through a right
angled prism as shown in the adjacent
diagram. State the angles of incidence at the faces ( A C ) and ( B C . ) Given critical
angle is ( 42^{circ} )
A . Angle of incidence at the face ( A C=45^{circ} ) and angle of
incidence at the face ( B C=90^{circ} )
B. Angle of incidence at the face ( A C=90^{circ} ) and angle of
incidence at the face ( B C=45^{circ} )
C. Angle of incidence at the face ( A C=45^{circ} ) and angle of
incidence at the face ( B C=0^{circ} )
D. Angle of incidence at the face ( A C=0^{circ} ) and angle of
incidence at the face ( B C=45^{circ} )
12
550Fill in the blanks:
A convex lens of ( _{text {一一一一一一 }} ) focal length gives a greater magnification than lenses of ( _{text {一一一一一一一 }} ) focal length.
A. short, short
B. short, long
c. long, short
D. Iong, long
12
551A person having eye problems should eat:
A. spinach, carrot
B. egg, milk
c. rice, banana
D. meat, apple
12
552Find the co-ordinates of image of point object P formed after two successive
reflection at concave mirror and then at
convex
12
553In case of a virtual and erect image, the magnification of a mirror is :
A. Positive
B. Negative
c. Unity
D. Infinity
12
554In a glass sphere, there is a small
bubble ( 22 times 10^{-2} mathrm{m} ) from its centre. If the
bubble is viewed along a diameter of the sphere, from the side on which it lies. The distance from the surface
where it appears is
(The radius of glass sphere is ( 25 times 10^{-2} )
( mathrm{m} ) and refractive index of glass is 1.5
A . 22.5 ( times 10^{-2} mathrm{m} )
B. 23.2 ( times 10^{-2} mathrm{m} )
( c cdot 26.5 times 10^{-2} mathrm{m} )
D. 20.2 ( times 10^{-2} mathrm{m} )
12
555During dispersion of light, the least dispersed light is :
A . violet
B. green
c. yellow
D. red
12
556When the length of a microscope tube increases, its magnifying power:
A. decreases
B. increases
c. does not change
D. can’t say
12
557Why we are not able to see our image on a cardboard even though it reflects light?
A. Because cardboard does not shine like mirror
B. Because cardboard is not as durable as mirror
c. Because cardboard’s surface is irregular
D. All
12
558A boy of height ( 1.5 mathrm{m} ) with his eye level at ( 1.4 mathrm{m} ) stands before a plane mirror of length ( 0.75 mathrm{m} ) fixed on the wall. The
height of the lower edge of the mirror above the floor is ( 0.8 mathrm{m} ). Then :
A. the boy will see his full image
B. the boy can’t see his hair
c. the boy can’t see his feet
D. the boy can see neither his hair nor his feet
12
559A ray of light passes through a prism as
shown in the figure.
The angle ( delta ) is known as:
A. Angle of deviation
B. Angle of dispersion
c. Angle of emergence
D. Angle of refraction
12
560Read the statements and mark the
correct one(s)
i. Braille cells are read from left to right. ii Each Braille character is made up of
six dots.
iii Braille can only be produced manually.
A. i and i i
B. ii and iii
c. i and iii
D. All are true
12
561A microscope:
A. converges light
B. diverges light
C . reflects light
D. refracts light
12
562Which of the following statements is
true?
A. Normal is always perpendicular to the mirror
B. Incident ray is always on the left side of the normal
c. Both A and B
D. None
12
563A double convex lens, made of a
material of refractive index ( mu_{1}, ) is
placed inside two liquids of refractive
indices ( mu_{2} ) and ( mu_{3} ) as shown. ( mu_{2}>mu_{1}>mu_{3} )
A wide, parallel beam of light is incident
on the lens from the left. The lens will
give rise to
A. a single convergent beam
B. two different convergent beams
c. two different divergent beams
D. a convergent and a divergent beam
12
564Three lenses of power ( +1.5 D ) and
( -0.5 D ) are kept in contact on their
principal axis. What is the effective power of the combination?
12
565The sun appears red at the time of sun-
rise and sun-set. This is because:
A. red colour is least scattered
B. red colour is most scattered
c. the sun is red in colour
D. our eyes can sense only red colou
12
566Q Type your question
z. Here z is the vertical distance inside
the slab, measured from the top. The slab is placed between two media with
uniform refractive indices ( n_{1} ) and ( n_{2} )
( left(>n_{1}right), ) as shown in the figure. A ray of
light incident with angle ( boldsymbol{theta}_{boldsymbol{i}} ) from
medium 1 and emerges in medium 2
with refraction angle ( theta_{f} ) with lateral
displacement ( l ) Which of the following statement(s) is (are) true?
This question has multiple correct options
A. ( l ) is dependent on ( n(z) )
B ( cdot n_{1} sin theta_{1}=left(n_{2}-n_{1}right) sin theta_{f} )
( mathbf{c} cdot n_{1} sin theta_{i}=n_{2} sin theta_{f} )
dependent of ( n )
12
567In a Newton’s Ring experiment, the diameter of the ( 20^{t h} ) dark ring was
found to be 5.82 mm and that the ( 10 t h )
ring 3.36 mm. If the radius of the
planoconvex lens is ( 1 m, ) calculate the wavelength of light used
12
568What is the angle between the incident and reflected rays when a ray of light is incident normally on a plane mirror?
A ( cdot 90^{circ} )
B . ( 45^{circ} )
( c cdot 180^{circ} )
D. ( 0^{circ} )
12
569A light is incident normally on a mirror. The value of angle of reflection will
be
( mathbf{A} cdot 90 )
B . 45
( c cdot 0^{c} )
D. 135
12
570Suppose you have focused on a screen the image of candle flame placed at the farthest end of the laboratory table using a convex lens. If your teacher suggests you to focus the parallel rays of the sun, reaching your laboratory table, on the same screen, what you are expected to do is to move the:
A. Lens slightly towards the screen
B. Lens slightly away from the screen
c. Lens slightly towards the sun
D. Lens and screen both towards the sun
12
571At what distance should an object be placed from a convex lens of focal length ( 18 mathrm{cm} ) to obtain an image at
( 24 c m ) if on the other side. What will be
the magnification produced in this
case?
12
572When a ray of light strikes a plane
mirror at an angle of ( 15^{circ} ) with the mirror, what will be the angle of reflection with respect to the normal?
A . 15
B. 30
( c cdot 75 )
D. None of these
12
573The bluish colour of water in deep sea is
due to:
A. the presence of algae and other plants found in water.
B. reflection of sky in water
c. scattering of light.
D. absorption of light by the sea
12
574Which instrument is used to view
astronomical bodies.
12
575An object is placed at a distance ( 2 f )
from the pole of a convex mirror of focal
length ( f . ) The linear magnification is:
A ( cdot frac{1}{3} )
B. ( frac{2}{3} )
( c cdot frac{3}{4} )
D.
12
576A light ray is incident normally on a plane mirror.
(a) What is the angle of incidence?
(b) What is the path of reflected ray?
A ( cdot(a) 180^{circ},(b) ) same as incident ray
в. ( (a) 180^{circ} )
( (b) ) opposite to incident ray
(b) opposite to incident ray
( mathbf{c} cdot(a) 0^{circ} )
D. ( (a) 0^{circ},(b) ) same as incident ray
12
577A car is fitted with a convex side-view
mirror of focal length ( 20 mathrm{cm} . ) A second
car ( 2.8 mathrm{m} ) behind the first car is
overtaking the first car at a relative speed of ( 15 mathrm{m} / mathrm{s} ). The speed of the image of the second car as seen in the mirror
of the first one is :
A ( cdot frac{1}{10} mathrm{m} / mathrm{s} )
в. ( frac{1}{15} mathrm{m} / mathrm{s} )
c. ( 10 mathrm{m} / mathrm{s} )
D. ( 15 mathrm{m} / mathrm{s} )
12
578Derive the Lens Maker’s formula.12
579Assertion
The frequencies of incident, reflected and refracted beam of monochromatic
light at the interface of two media are
same
Reason
The incident, reflected, refracted rays are coplanar.
A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true and reason is not the correct explanation of assertion
c. If assertion is true but reason is false
D. If both assertion and reason are false
12
580A rod of length ( 10 mathrm{cm} ) lies along the principal axis of a concave mirror of focal length ( 10 mathrm{cm} ) in such away that the end closer to the pole is ( 20 mathrm{cm} ) away
from it. Find the length of the image.
A . ( 2 mathrm{cm} )
B. ( 4 mathrm{cm} )
( c cdot 5 mathrm{cm} )
D. ( 6 mathrm{cm} )
12
581Assertion
The right-handed coordinate system is converted into left-handed coordinate
system by a plane mirror and
Reason
Plane mirror produces the reversal in the direction of normal
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason are correct
12
582The light ray which strikes any polished surface at some angle is called:
A . reflected ray
B. incident ray
c. normal ray
D. none of these
12
583A Nicol prism is based on the principle
of.
A. Refraction
B. Scattering
c. Dichroism
D. Double refraction
12
584A converging beam of light travelling in air converges at a point ( P ) as shown in the figure. When a glass sphere of refractive index 1.5 is introduced in
between the path of the beam, calculate
the position of the image. Also draw the ray diagram for the image formed
12
585Why do stars twinkle?12
586Match List-I with List- II and select the
answer using the codes given below the
lists:
begin{tabular}{lll|l}
List-I & multicolumn{3}{l} { List-II } \
A. & Microscope & 1. & To see objects on the surface by an observer in a trench \
B. & Telescope & 2. & To see small objects \
C. & Periscope & 3. & To see distant objects \
D. & Camera & 4. & To take photographs of objects
end{tabular}
( A )
( begin{array}{llll}2 & 1 & 4 & 3end{array} )
B. ( 1 quad 2 quad 3 quad 4 )
( begin{array}{llll}mathbf{c} cdot 2 & 3 & 4 & 1end{array} )
( begin{array}{ll}text { D. } 2 & text { (年) } 3end{array} )
12
587(i) Why does the Sun appear red at
sunrise?
(iii) Name the subjective property of
light related to its wavelength.
12
588What are the characteristics of the final
image formed by a compound microscope?
12
589Very fine particles mainly scatter coloured light.
A . Red
B. Blue
c. Green
D. Yellow
12
590A ( 4 mathrm{cm} ) tall object is placed on the
principal axis of a convex lens. The distance of the object from the optical
centre of the lens is ( 12 mathrm{cm} ) and its sharp image is formed at a distance of ( 24 mathrm{cm} ) from it on a screen on the other side of
the lens. If the object is now moved a
little away from the lens, in which way (towards the lens or away from the lens) will he have to move the screen to get a
sharp image of the object on it again? How will the magnification of the image be affected?
12
591Match the elements of table I and II.
begin{tabular}{ll}
Table I & table II \
a) Myopia & i) Bifocal len \
b) Hypermetropia & ii) Cylindrical lens \
c) Presbyopia & iii) Concave lens \
d) Astigmation & iv) Convex lens \
hline
end{tabular}
( A cdot a- ) iii, b – iv, c-i, d -ii
B. a – iv, b – iii, c-i, d- i i
( c cdot a-i, b-i i, c-i i i, d-i v )
D. a – ii, b – iv, c-i, d- iii
12
592When the light enters from air to glass, which colour the angle of deviation maximum?
A. Red
B. Yellow
c. Blue
D. Violet
12
593A square of side ( 3 mathrm{cm} ) is located at a
distance ( 25 mathrm{cm} ) from a concave mirror
of focal length ( 10 mathrm{cm} ). The center of square is at the axis of the mirror and the plane is normal to axis of mirror. The
area enclosed by the image of the square is :
A ( cdot 4 c m^{2} )
в. ( 6 mathrm{cm}^{2} )
c. ( 16 mathrm{cm}^{2} )
D. ( 36 c m^{2} )
12
594Select the odd one out w.r.t. the type of reflection of incident light (wood, steel, silver, mirror, graphite)
A. mirror
B. woodd
c. silver
D. steel
12
595The minimum distance between an
object and its real image formed by a
convex lens is :
A ( cdot frac{2}{3} f )
B . ( 2 f )
c. ( frac{5}{2} f )
D. ( 4 f )
12
596Two identical glass ( left(mu_{g}=3 / 2right) )
equiconvex lenses of focal length ( f ) are
kept in contact. The space between the two lenses is filled with water ( left(mu_{w}=right. )
4/3). The focal length of the combination is
( A cdot f )
в. ( frac{f}{2} )
c. ( frac{4 f}{3} )
D. ( frac{3 f}{4} )
12
597An old man cannot see objects closer than ( 1 mathrm{m} ) from the eye clearly. Name the
defect of vision he is suffering from. How can it be corrected? Draw ray
diagram for the
(i) defect of vision and
also
(ii) for its correction.
12
598A persons sees clearly at a distance of
100cm, then power of lens used to see
object at ( 40 mathrm{cm} ) is
( A .3 D )
в. ( -3 D )
c. ( -1.5 D )
D. ( +1.5 D )
12
599An object of size ( 7 mathrm{cm} ) is placed at ( 27 mathrm{cm} )
in front of a concave mirror of focal
length ( 18 mathrm{cm} . ) At what distance from the mirror should a screen be placed, so that a sharp focused image can be obtained ? Find the size and the nature
of the image.
12
600If you raise your right hand in front of a plane mirror, what will you see in it?
A. You have raised your right hand
B. You have raised your left hand
c. You have lowered your right hand
D. You have lowered your left hand
12
601Rainbow is not caused due to:
A. Reflection of light
B. Refraction of light
C. Dispersion
D. Scattering
12
602Which of the following quantity does not have any unit?
A. Velocity of light
B. Light year
c. Magnification
D. Power of a lens
12
603A ray of light passing through a prism having ( mu=sqrt{2} ) suffer minimum deviation. It is found that angle of incidence is double the angle of
refraction within the prism. Find angle of the prism.
12
604An object is held ( 20 c m ) away from a
converging lens of focal length ( 10 mathrm{cm} ) Find the position of the image formed.
12
605A coin kept in a container and not visible can be viewed by pouring water into the container. It happens because
of the
A. Reflection of light.
B. Refraction of light
c. variable refractive index of water.
D. None of the above
12
606Draw a schematic diagram of a reflecting telescope (Cassegrain) Write its two advantages over a refracting telescope.12
607Two symmetrical double convex lenses A and B have same focal length,but the radii of curvature differ so that ( boldsymbol{R}= )
( 0.9 R . ) If ( mu=1.63 ) find the ( mu_{B} )
12
608The equiconvex lens has focal length ( boldsymbol{f} )
If it is cut perpendicular to the principal axis passing through optical centre, then focal length of each half is
A ( cdot frac{f}{2} )
B. ( f )
( c cdot frac{3 f}{2} )
D. ( 2 f )
12
609A convex lens of focal length ( f ) is cut into two halves as shown. Light rays parallel to the principal axis are incident on one
half of the lens ( left(operatorname{say} L_{1}right) . ) This will
form an image at :
( A cdot f )
B. ( f / 2 )
( c cdot 2 f )
D. ( f / )
12
610The distance at which an object should be placed in front of a convex lens of
focal length ( 10 mathrm{cm} ) to obtain a real
image double the size of object will be:
( A .30 mathrm{cm} )
B. ( 15 mathrm{cm} )
( c cdot 5 mathrm{cm} )
D. ( 10 mathrm{cm} )
12
611The electromagnetic waves
A. travel with the the speed of sound.
B. travel with the the same speed in all media.
C . travel in free space with the speed of light.
D. do not travel through a medium.
12
612The curved surface of a shining spoon could be considered as a
A. Curved mirror
B. Plane mirror
c. concave mirror only
D. None
12
613A ray of light enters from air to a
medium ( X . ) The speed of light in the
medium is ( 1.5 times 10^{8} m / s ) and the speed
of light in air is ( 3 times 10^{8} m / s ). Find the
Refractive index of the medium ( boldsymbol{X} )
12
614The focal length of a concave mirror is ( 50 mathrm{cm} ) where an object is to be placed so that its image is two times magnified, real and inverted:
A. ( 75 mathrm{cm} )
B. 72 cm
( c cdot 63 mathrm{cm} )
D. 50 cm
12
615Rays of light from Sun falls on a
biconvex lens of focal length ( f ) and the
circular image of Sun of radius ( r ) is formed on the focal plane of the lens. Then
A. Area of image is ( pi r^{2} ) and area is directly proportional of ( f )
B. Area of image is ( pi r^{2} ) and area is directly proportional to ( t^{2} )
c. Intensity of image increases if ( f ) is increased
D. If lower half of the lens is covered with black paper, area will become half
12
616What is the angle of incidence when the incident ray is normal to the interface or boundary separating two media?
A ( cdot 0^{circ} )
B. ( 90^{circ} )
( c cdot 180^{circ} )
D. ( 45^{circ} )
12
617Which of the following is a correct way
by which we can take care of our eyes?
A. Reading the books by bringing as near as possible
B. Washing our eyes frequently
C. Using as much light as possible while studying
D. Looking directly at sun every morning
12
618In which direction does he move the
lens to focus the flame on the screen?
12
619A ray of light passes through an equilateral prism (refractive index 1.5 ) such that angle of incidence is equal to angle of emergence and the latter is equal to ( 3 / 4^{t h} ) of the angle of prism. The angle of deviation is
A .60
B. ( 30^{circ} )
c. 45
D. ( 120^{circ} )
12
620A number of thin prism of prism angle ( A ) and refractive index ( mu ) are arranged
on periphery of circle such that any light ray entering from one prism move along a regular polygon
A. number of prism used will be ( frac{4 pi}{(mu-1) A} )
B. If ( A ) is rational, ( mu ) must be rational
c. if ( A ) is rational, ( mu ) must be irrational
D. If ( A ) is irrational, ( mu ) must be irrational
12
621A perfectly reflecting solid sphere of radius ( r ) is kept in the path of a parallel beam of light of large aperture. If the beam carries an intensity I, find the force exerted by the beam on the sphere.12
622Which of the following is Shell’s law
A. ( n_{1} ) sini ( =n_{2} ) sinr
В ( cdot n_{1} / n_{2}=sin r times ) constant
c. ( n_{2} / n_{1}=sin r / sin i )
D. ( n_{2} sin i= ) constant
12
623What type of mirrors do we use in our
houses to see ourselves?
A. Convex mirror
B. Plane mirror
c. Concave mirror
D. Any of the above
12
624The image of an object formed by a convex lens when the object is placed between the lens and the focal point is –
A. Virtual and inverted
B. Real and magnified
c. Real and diminished
D. Virtual and magnified
12
625Periscope works on the principle of:
A. refraction of light
B. reflection of light
c. diffraction of light
D. scattering of light
12
626Colours of rainbow are in VIBGYOR
sequence:
A . True
B. False
12
627A container contains water up to a
height of ( 20 mathrm{cm} ) and there is a point
source at the centre of the bottom of the
container. A rubber ring of radius ( r ) floats centrally on the water. The ceiling of the room is ( 2.0 m ) above the water
surface.
(a) Find the radius of the
shadow of the ring formed on the ceiling if ( r=15 mathrm{cm} )
(b) Find the maximum
value ( r ) for which the shadow of the ring
is formed on the ceiling. Refrective index of water ( =mathbf{4} / mathbf{3} )
12
628Bi-focal lens is required to correct:
A. cataract
B. astigmatism
c. myopia
D. presbyopia
12
629Four identical mirrors are made to
stand vertically to form a square arrangement as shown in a top view. A ray starts from the midpoint M of mirror Ad and after two reflections reaches
cornor D. Then, angle ( theta ) must be
A ( cdot tan ^{-1}(0.75) )
B ( cdot cot ^{-1}(0.75) )
c. ( sin ^{-1}(0.75) )
D cdot ( cos ^{-1}(0.75) )
12
630What do you mean by “Rectilinear
Propagation” of Light?
A. Light travels in a straight line
B. Light travels in a curved path
C. Light exhibits dual nature of particle and wave
D. Light gets deviated when it moves in another medium
12
631A biconvex lens of focal length ( 15 mathrm{cm} ) is in front of a plane mirror. The distance between the lens and the mirror is 10
( mathrm{cm} . mathrm{A} ) small object is kept at a distance of ( 30 mathrm{cm} ) from the lens. The final image is
A. Virtual and at a distance of ( 16 mathrm{cm} ) from the mirror
B. Real and at a distance of ( 16 mathrm{cm} ) from the mirror
c. Virtual and at a distance of ( 20 mathrm{cm} ) from the mirror
D. Real and at a distance of ( 20 mathrm{cm} ) from the mirro
12
632How does the power of lens vary with its
focal length?
12
633A reflecting surface is represented by the equation ( Y=frac{2 L}{pi} sin left(frac{pi x}{L}right), 0 leq )
( x leq L . ) A ray travelling horizontally
becomes vertical after reflection. The
coordinates of the point(s) where this ray is incident is
A . True
B. False
12
634VUJ
7. The aperture of the objective lens of a telescope is made
large so as to
(a) increase the magnifying power of the telescope
(b) increase the resolving power of the telescope
(c) make image aberration less
(d) focus on distant objects
(AIEEE 2003)
12
635The nature of image of a candle flame located ( 40 mathrm{cm} ) from a concave spherical mirror is real, inverted and magnified
four times. Then the radius of curvature
of the mirror is:
( A .32 mathrm{cm} )
B. ( 64 mathrm{cm} )
c. ( 48 mathrm{cm} )
D. ( 80 mathrm{cm} )
12
636Iris : controls the size of the pupil ::
: regulates the amount of light entering the eye
A. Pupil
B. Lens
c. Retina
D. cornea
12
637An experiment is performed to find the refractive index of glass using a travelling microscope. In this experiment distances are measured by:
A. a screw gauge provided on the microscope
B. a standard laboratory scale
c. a vernier scale provided on the microscope
D. a meter scale provided on the microscope
12
638A clock fixed on a wall shows time 04:
( 25: 37 . ) Its image in a plane mirror shows:
( A cdot 07: 30: 33 )
B. 07:43: 32
c. 07: 35: 22
D. 43: 27: 36
12
639Refractive indices of 2 different media
with separating boundary at the
diagonal of rectangular glass slab are
shown. Total angle of deviation of the ray
as shown in the figure, when it emerges
in air is :
air
A ( cdot 120^{circ} )
B. 90
( c cdot 60^{circ} )
D ( .45^{circ} )
( E cdot 30 )
12
640For the same angle of incidence, the
angles of refraction in media ( mathrm{P}, mathrm{Q}, mathrm{R} ) and
( mathrm{S} ) are ( 50^{circ}, 40^{circ}, 30^{circ}, 20^{circ}, ) respectively. The
speed of light is minimum in medium:
( A cdot P )
B.
( c cdot R )
( D cdot s )
12
641A ray of light is incident at an angle ( i ) on
a glass slab of refractive index ( mu ). The
angle between reflected and refracted
light is ( 90^{circ} . ) Then, the relationship
between i and ( mu ) is :
A ( cdot i=tan ^{-1}left(frac{1}{mu}right) )
В. ( tan i=mu )
( mathrm{c} cdot sin i=mu )
D. ( cos i=mu )
12
642The rays of light, which are not paralle to each other and spread out from a point, are called and
a bundle of rays, which are parallel to
one another, is called
A. parallel beam of light, convergent rays
B. divergent rays, convergent rays
c. convergent rays, parallel beam of light
D. divergent rays, parallel beam of light
12
643Doctor has prescribed a lens having power ( +1.5 D . ) What would be the focal
length of the lens? What is the type of
lens and what must be the defeat of
vision?
12
644Define the magnifying power of a compound microscope when the final image is formed at infinity. Why must both the objective and the eyepiece of a compound microscope have short focal lengths? Explain.12
645A convex lens forms a real image three
times larger than the object on a screen Object and screen are moved until the
image becomes twice the size of the
object. If the shift of the object is ( 6 mathrm{cm} )
The shift of screen is
( mathbf{A} cdot 36 c m )
B. ( 72 mathrm{cm} )
( mathbf{c} cdot 18 c m )
D. 9 cm
12
646A light ray is incident perpendicular to
one face of a ( 90^{0} ) prism and is totally intemally reflected at the glass-air
interface. If the angle of reflection is ( 45^{circ} )
we conclude that the refractive index n
4
B ( . n>sqrt{2} )
( c cdot n>frac{1}{sqrt{2}} )
D. ( n<sqrt{2} )
12
647A thin lens of focal length ( 10 mathrm{cm} ) is cut
into two equal halves and are kept as
shown in figure. It an object ( boldsymbol{O} ) is placed
at distance ( 10 mathrm{cm} ) from the optical
centre of combination. then the
distance of image from object will be
( A cdot 5 mathrm{cm} )
B. 7.5 ( mathrm{cm} )
( c cdot 10 mathrm{cm} )
D. 20 cm
12
648“The magnification produced by a spherical mirror is – ( 3 ” ). List four informations you obtain from this statement about the mirror/image.12
649In what cases, does a light ray not deviate at the interface of two media?12
65051. A plano-convex lens fits exactly into a plano-concave lens.
Their plane surfaces are parallel to each other. If the lenses
are made of different material of refractive indices , and
Hy and R is the radius of curvature of the curved surface
of the lenses, then focal length of the combination is
(a)
(b)
2R
– H2
10
R
M₂ – Mi
R
2-(M + M₂
24 – M₂)
12
651The magnification of a magnifying lens of focal length ( 5 mathrm{cm} ) is : (final image is at ( infty) )
( A )
B. 2
( c cdot 3 )
D. 5
12
652A denser medium of refractive index 1.5
has a concave surface of radius of
curvature ( 12 mathrm{cm} . ) An object is situated in the denser medium at a distance of 9
( mathrm{cm} ) from the pole. Locate the image due
to refraction in air
A. A real image at ( 8 mathrm{cm} )
B. A virtual image at ( 8 mathrm{cm} )
c. A real image at ( 4.8 mathrm{cm} )
D. A virtual image at ( 4.8 mathrm{cm} )
12
653The angle between the two refracting surface of a prism is called angle of :
A. incidence
B. base
c. dispersion
D. prism
12
654Which of the following is a natural source of light?
A. Electric lamp
B. Electric filament
c. Torch light
D. Sunlight
12
655The inability among the elderly to see nearby objects clearly because of the weaking of the ciliary muscles is called
A. far-sightedness
B. near-sightedness
c. presbyopia
D. astigmatism
12
656A thin equiconvex lens of refractive index ( 3 / 2 ) is placed on a horizontal plane mirror as shown in figure. The
space between the lens and the mirror
is filled with a liquid of refractive index 4/3. It is found what when a point object is placed ( 15 mathrm{cm} ) above the lens on its
principal axis, the object coincides with its own image.
If another liquid is filled instead of
water, the object and the image coincide at a distance ( 25 mathrm{cm} ) from the
lens. Calculate the refractive index of
the liquid.
( mathbf{A} cdot 1.6 )
в. 2.6
( c .2 .8 )
D. 3.2
12
657The relation between ( u, v ) and ( f ) for a
mirror is given by
A ( cdot f=frac{u times v}{u-v} )
в. ( f=frac{2 u times v}{u+v} )
c. ( _{f}=frac{u times v}{u+v} )
D. ( f=frac{u-v}{u+v} )
12
658A glass hemisphere of radius ( R ) and of
material having refractive index 1.5 is
silvered on its flat face as shown in
figure. A small object of height ( h ) is
located at a distance ( 2 R ) from the
surface of hemisphere as shown in figure. The final image will form.
A. At a distance of ( R ) from silvered surface, on the right side
B. On the object itself
C. At hemisphere surface
D. At a distance of ( 2 R ) from the silvered surface, on left
side
12
659In a healthy human eye, the focussing is
done by the
A. To and fro movement of the eye-lens
B. Changing the curvature of the retina
C. Change in the convexity of the lens through ciliary tubes
D. Change in the refractive index of the eye fluid
12
660Two plane mirrors are placed parallel to each other at a distance Lapart. A point
object 0 placed between them, at a distance L/3 from one mirror. Both
mirrors form multiple images. The distance between any two images
cannot be
A ( cdot frac{3 L}{2} )
в. ( frac{2 L}{3} )
( c cdot 2 L )
D. ( L )
12
661A gun of mass ( m_{1} ) fires a bullet of mass
( m_{2} ) with a horizontal speed ( v_{0} . ) The gun
is fitted with a concave mirror of focal
length ( f ) facing toward a receding
bullet. Find the speed of separations of
the bullet and the image just after the
gun was fired.
12
662Which is smaller?2497 or 259712
663The angle between an incident ray and
the mirror is ( 60^{circ} . ) Then the total angle turned by the ray of light is:
A ( .60^{circ} )
B . ( 120^{circ} )
( c cdot 30^{circ} )
D. ( 90^{circ} )
12
664In the figure shown the radius of
curvature of the left ( & ) right surface of
the concave lens is ( 10 mathrm{cm} & 15 mathrm{cm} )
respectively. The radius of curvature of
the mirror is ( 15 mathrm{cm} )
A. Equivalent focal length of the combination is ( 18 mathrm{cm} )
B. Equivalent focal length of the combination is ( +36 mathrm{cm} )
c. The system behaves like a concave mirror
D. The system behaves like a convex mirror
12
665Describe the construction of a
compound microscope. Derive an expression for its total magnification. Draw a ray diagram for the formation of image by a compound microscope.
12
666A light moves from denser to rarer medium, which of the following is
correct?
A. Energy increases
B. Frequency increases
C. Phase changes by ( 90^{circ} )
D. Velocity increases
12
667Which of the following phenomenon is involved in Tyndall effect?
A. Reflection of light.
B. Refraction of light
c. scattering of light.
D. Magnification of light.
12
668A drop of water is placed on a glass plate. A double convex lens having radius of curvature of each surface 20
( mathrm{cm} ) is placed on it. The focal length of water lens ( left(mu text { for water }=frac{3}{4}right), ) will be
A . -0.20
B. -0.60 ( mathrm{m} )
( c .0 .30 )
D. ( 0.40 mathrm{m} )
12
669In the diagram shown, a light ray is incident on the lower medium boundary
at an angle if ( 45^{circ} ) with the normal.
Which of the following statements is
are true?
‘his question has multiple correct options
A ( cdot ) If ( mu_{2} / sqrt{2} ), then angle of deviation is 45
B. If ( mu_{2} / sqrt{2} ), then angle of deviation is ( 90^{circ} )
( mathrm{C} cdot ) If ( mu_{2} / sqrt{2}, ) then angle of deviation is ( 135^{circ} )
D. If ( mu_{2} / sqrt{2} ), then angle of deviation is 0
12
670Assertion: By roughening the surface of
a glass sheet its transparency can be
reduced.

Reason: Glass sheet with rough surface absorbs more light.
A. Both assertion and reason are true and reason is the correct explanation of assertion
B. Both assertion and reason are true but the reason is not the correct explanation of assertion
c. Assertion is true but reason is false
D. Both the assertion and reason are false
E. Reason is true but assertion is false

12
671What is known as linear magnification of spherical mirrors?
A. Ratio of size of image to size of object
B. Ratio of shape of image to size of object
c. Ratio of size of image to shape of object
D. None
12
672Magnification produced by a concave lens is always:
A. less than 1
B. more than 1
c. equal to 1
D. equal to 2
12
67360. A convex lens forms an image of an object placed 20 cm
away from it at a distance of 20 cm on the other side of
the lens. If the object is moves 5 cm toward the lens, the
image will be
(a) 5 cm toward the lens
(b) 5 cm away from the lens
(c) 10 cm toward the lens
(d) 10 cm away from the lens
12
674Sunlight of intensity ( 1.3 k W m^{-2} ) is
incident normally on a thin convex lens of focal length ( 20 mathrm{cm} ). Ignore the energy loss of light due to the lens and assume
that the lens aperture size is much smaller than its focal length. The
average intensity of light, in ( k W m^{-2}, ) at
a distance ( 22 c m ) from the lens on the
other side is
12
675A nearsighted person cannot be see beyond ( 25 mathrm{cm} . ) Assuming that the separation of the glass from the eye is
( mathbf{1} c m, ) find the power of lens needed to see distant objects.
12
676When light travels from one medium into another it suffers
A. Reflection
B. Refraction
c. Dispersion
D. None of these
12
677Where must an object be placed in front of a convex lens so that the image formed is at infinity?12
678Light is a form of energy.
A. True
B. False
12
679Name the type of lens used to correct
this defect.
12
680Mark correct option or options:
A. The minimum distance between a real image and the real object in concave mirror is zero
B. The minimum distance between a real object and real image in concave mirror is greater than ( 4 f ), where ( f ) is focal length of the lens
C. The focal length of concave mirror depends upon the wavelength of light incident on it
D. The focal length of mirror depends upon medium infront of the mirror
12
681The unit of magnification is :
( mathbf{A} cdot m )
B. ( m^{2} )
( mathrm{c} cdot m^{-1} )
D. it has no units
12
682Concave and convex lenses, each have
the same focal length ( 20 mathrm{cm} ) and they
are put in contact to form a
combination lens. This combination
lens is used to view an object of ( 5 mathrm{cm} )
length, kept at a distance ( 20 mathrm{cm} ) from
the lens combination. As compared to
the object the image will be
A. Magnified and inverted.
B. Reduced and erect.
C. of the same size as the object and erect.
D. of the same size as the object but inverted.
12
683A concave mirror produces 10 times enlarged image (real) of an object
placed ( 1 c m ) in front of it. Where is the
image located?
A ( .5 mathrm{cm} )
B. ( -10 mathrm{cm} )
c. ( -5 c m )
D. ( 10 mathrm{cm} )
12
684A converging beam of rays is incident on a diverging lens. Having passed through the lens the rays intersect at a point ( 15 mathrm{cm} ) from the lens. If the lens is removed, the point where the rays meet will move ( 5 mathrm{cm} ) closer to the mounting
that holds. Find the focal length ( (text { in } mathrm{cm}) ) of the lens without sign.
12
685Complete the refracted ray in the
flowing ray diagram
12
686The sideways reversal of the image by plane mirror is called:
A. lateral inversion
B. parallax
c. optical illusion
D. magic
12
687A concave lens of focal length ( boldsymbol{f} ) produces an image ( (1 / n) ) times the size of the object. The distance of the object from the lens is
A ( cdot(n+1) f )
в. ( frac{(n-1)}{n} f )
c. ( frac{(n+1)}{n} f )
D. ( (n-1) f )
12
688The angle between the normal and the
reflected ray is ( 40^{circ} . ) Then the angle of incidence will be
A ( .50^{circ} )
B. ( 20^{circ} )
( c cdot 40^{circ} )
D. Can’t be predicted
12
689Fruits and vegetables advisable for
good vision are:
A. apple, banana, carrots
B. mango, papaya, carrots
c. cabbage, sunflower oil, groundnut
D. all fruits and vegetables
12
690Fill in the blanks.
a) For a motor: a permanent magnet, then for a commercial motor:
b) Focal length of a lens: metre, then for
power of a lens:
12
691The reflecting surface of a plane mirror is vertical. A particle is a project in a vertical plane also perpendicular to the mirror the initial speed of the particle
is ( 10 mathrm{m} / mathrm{s} ) and the angle of project ( 60^{circ} )
from the normal of the mirror. the point of projection is at a distance ( 5 mathrm{m} ) from particle moves towards the mirror.just before the particle touches the mirror.
the velocity of approving of the particle
and the image is:
A. ( 12 mathrm{m} / mathrm{s} )
B. ( 5 mathrm{m} / mathrm{s} )
c. ( 10 mathrm{m} / mathrm{s} )
D. ( 5 sqrt{5} ) m/s
12
692Sun ray are incident at an angle of ( 24^{circ} )
with the horizontal. How can they be directed parallel to the horizon using a plane mirror?
12
693(a) Write the necessary conditions for the phenomenon of total internal
reflection to occur.
(b) Write the relation between the
refractive index and critical angle for a given pair of optical media.
12
694In passing through a boundary, refraction will not take place if This question has multiple correct options
A. light is incident normally on the boundary
B. the indices of refraction of the two media are same
c. the boundary is not visible
D. angle of incidence exceeds the critical angle
12
695Pick the incorrect statement from the
following:
A. Iris is the part of the eye which gives it, its distinctive colour
B. The most comfortable distance at which one can read
with a normal eye is about ( 50 mathrm{cm} )
C. If still images of a moving object are flashed on the eye at a rate faster than ( 16 / s ), then, the eye perceives this object as moving
D. Eye lens becoming cloudy is called cataract
12
696A point object is placed at a distance of
( 25 mathrm{cm} ) from a convex lens of focal length
( 20 mathrm{cm} . ) If a glass slab of thickness ( t ) and
refractive index 1.5 is inserted between
the lens and the object, the image is formed at infinity. The thickness ( t ) is
( mathbf{A} cdot 10 mathrm{cm} )
в. ( 5 mathrm{cm} )
( mathbf{c} cdot 20 c m )
D. ( 15 mathrm{cm} )
12
697As the beam enters the medium, it will
A . diverge
B. converge
c. diverge near the axis and converge near the periphery
D. travel as a cylindrical beam
12
69839. A ray of light passes from glass, having a refractive indey
of 1.6, to air. The angle of incidence for which the angle
of refraction is twice the angle of incidence is
(a) sin-
(b) sin-
12
699What is reflection? Write the laws of
reflection.
12
700When a pencil is partly immersed in water, the pencil appears to bend at the surface. Reason behind this is:
A . Reflection
B. Refraction
c. Total internal reflection
D. Diffraction
12
701A light ray is incident on a transparent sphere of index ( =sqrt{2}, ) at an angle of
incidence ( =45 . ) What is the deviation of
a tiny fraction of the ray, which enters the sphere, undergoes two internal reflections and then refracts out into air
( ? )
A . 270
B. 240
( c . ) 30
D. 180
12
702How can we change a camera from ( boldsymbol{F} / mathbf{4} )
( operatorname{to} F / 5.6 ? )
A. Increase the aperture to 2 time keeping the focal distance constant
B. Increase the aperture to ( sqrt{2} ) time keeping the focal distance constant
C . Increase the aperture to ( frac{1}{2} ) time keeping the focal
distance constant
D. Increase the aperture to ( frac{1}{sqrt{2}} ) time keeping the focal
distance constant
12
703Air is not visible because it:
( mathbf{A} cdot ) is nearly a perfectly transparent substance
B. neither absorbs nor reflects light
C. transmits whole of light
D. follows all of the above
12
704How will you design a shaving mirror
assuming that a person keeps it ( 10 mathrm{cm} ) from his face and view the magnified image of the face of the closest
comfortable distance of ( 25 mathrm{cm} ). The
radius of curvature of the mirror would
then be:
( mathbf{A} cdot 24 mathrm{cm} )
B. ( -60 c m )
( c .-24 c m )
D. ( 30 mathrm{cm} )
12
705The relation between ( u, v ) (u is the object distance and v is the image distance ) and f for mirror is given by:
A ( cdot f=frac{u v}{u-v} )
B. ( f=frac{2 u times v}{u+v} )
c. ( f=frac{u times v}{u+v} )
D. none of these
12
706Assertion: There exist two angles of
incidence for the same magnitude of deviation (except minimum deviation)
by a prism kept in the air. Reason: In a prism kept in the air, a ray is incident on the first surface and
emerges out of the second surface. Now
if another ray is incident on second. surface (of the prism) along the
previous emergent ray, then this ray emerges out of the first surface along
the previous incident ray. This principle is called the principle of reversibility of light.
A. Both Assertion and Reason are correct and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
707The human eye forms the image of an
object at its
A. cornea
B. iriss
c. pupil
D. retina
12
708A water film is formed on a glass-block. A light ray is incident on water film from air at an angle of ( 60^{circ} ) with the normal. The angle of incidence on glass slab is ( left(mu_{g}=1.5, mu_{w}=frac{4}{3}right) )
A ( cdot sin ^{-1}left(frac{3 sqrt{3}}{8}right) )
в. ( sin ^{-1}left(frac{1}{sqrt{3}}right) )
c. ( sin ^{-1}left(frac{4 sqrt{3}}{9}right) )
D. ( sin ^{-1}left(frac{9 sqrt{3}}{16}right) )
12
709An object is placed ( 25 mathrm{cm} ) from a convex lens whose focal length is ( 10 mathrm{cm} ). The
image distance is ( (50 c m, 16.66 c m, 6.66 c m, 10 c m) )
12
710State whether true or false.
The line drawn perpendicular to the mirror at the point of incidence is called the reflected ray.
A. True
B. False
12
711A diverging meniscus lens has a focal length of ( -20 mathrm{cm} . ) If the lens is held 10 ( mathrm{cm} ) from the object, the magnification is :
A . -0.667
B. +0.667
( c cdot-2 )
( D cdot+2 )
12
712why does the sky sometimes appear white?12
713Why the angle of incidence must not be
less then ( 30^{circ} ) while calculating angle of minimum deviation?
12
714An object kept on the principal axis and infront of a spherical mirror, is moved along the axis itself. Its lateral magnification ( mathrm{m} ) is measured, and plotted versus object distance |ul for a
range of ( u ), as shown in fig. The magnification of the object when it is placed at a distance ( 20 mathrm{cm} ) in front of
the mirror is:
( A cdot- )
B.
( c )
D. 2
12
715Angle of reflection is the angle between reflected ray and the ……… (incident ray, normal).12
716Explain why the planets do not twinkle.12
717The diagram alongside shows the
refraction of a ray of light from air to a
liquid. Angle of refraction is:
A ( cdot 60^{circ} )
B . ( 15^{circ} )
( c .30^{circ} )
D. ( 45^{circ} )
12
718If the light moving in a straight line bends by small but fixed angle while entering in different medium, it may be a case of :
A. reflection of light
B. refraction of light
c. scattering of light
D. dispersion of light
12
719The focal length of a convex lens of
glass ( (mu=1.5) ) is ( 2 c m . ) The focal length of the lens when immersed in a liquid of
refractive index 1.25 will be :
A ( .5 mathrm{cm} )
B. ( 2.4 mathrm{cm} )
( c .1 c m )
D. ( 4 c m )
12
720After tracing the path of a ray of light
passing through a rectangular glass slab for four different values of the
angle of incidence, a student reported his observations in tabular form as
given below:
( <mathrm{e} ) s.No ( begin{array}{lccc}text { । } & 30^{0} & 19^{0} & 29^{0} \ text { ॥ } & 40^{0} & 28^{0} & 40^{0} \ text { ॥। } & 50^{0} & 36^{0} & 50^{0} \ text { । } & 60^{0} & 40^{0} & 59^{0}end{array} )
The best observation is :
( A )
B. II
( c )
D. IV
12
721Choose the correct answer from
alternatives given

The mixture of a pure liquid and a
solution in a long vertical column (i.e, horizontal dimensions
A ( -frac{1}{d}left(frac{d u}{d y}right) mu )
B ( cdot frac{d}{h}left(frac{d u}{d y}right) )
c. ( left(frac{d u}{d y}right) )
” ( -frac{1}{mu}left(frac{d u}{d y}right) d )

12
722In ray diagrams, what is the least number of rays needed to find the position of an image formed by a lens?
( A cdot 4 )
B. 3
( c cdot 2 )
D.
12
723Choose the correct relation between
( u, v ) and ( r ) for a spherical mirror, where
( r ) is radius of curvature.
A ( cdot r=frac{2 u v}{u+v} )
B. ( r=frac{2}{u+v} )
c. ( r=frac{2(u+v)}{(u v)} )
D. ( r=frac{2 u v}{u-v} )
12
724Mark the option which correctly
differentiates between solar and lunar
eclipse:
A. When the moon comes in between the earth and the
sun and if all the three are in same straight line, solar eclipse occurs. And when the earth comes in between the sun and the moon and if all the three are in same straight line, lunar eclipse occurs.
B. When the earth comes in between the sun and the
moon and if all the three are in same straight line, solar eclipse occurs. And, when the earth comes in between the sun and the moon and if all the three are
in same straight line, lunar eclipse occurs.
C. Both A and B are wrong.
D. Sun’s shadow causes solar eclipse and moon’s shadow causes lunar eclipse.
12
725An air bubble is inside water. The refractive index of water is ( frac{4}{3} . ) At what distance from the air bubble should a
point object be placed so as to form a real image at the same distance from
the bubble?
A . 2 R
B. 3R
c. 4 R
D. The air bubble cannot form a real image
12
726The ( X-Z ) plane separates two media
( A ) and ( B ) of refractive indices ( mu_{A}=1.5 )
and ( mu_{B}=2 . ) A ray of light travels from
( A ) to ( B ), its direction in two media are
given by unit vectors. ( hat{boldsymbol{u}}_{boldsymbol{A}}=boldsymbol{a} hat{boldsymbol{i}}+boldsymbol{b} hat{boldsymbol{j}} ) and
( hat{boldsymbol{u}}_{B}=boldsymbol{c} hat{boldsymbol{i}}+boldsymbol{d} hat{boldsymbol{j}} ) respectively, then :
( ^{A} cdot frac{a}{c}=frac{4}{3} )
B. ( frac{a}{c}=frac{3}{4} )
c. ( frac{b}{d}=frac{4}{3} )
D. ( frac{b}{d}=frac{3}{4} )
12
727What happens to the size of the image of the flame formed on the screen?12
728Fill in the blanks
The eye lens can change its focal length
due to working of
muscles.
12
729How are non luminous objects visible to eye?
A. Non-luminous objects give away light
B. Non-luminous objects reflect the light falling on them
C. Non-luminous objects disperse the light falling on them
D. None of the above
12
730When a lens is inserted between an
object and a screen which are at a fixed distance apart, the size of the image in either ( 6 mathrm{cm} ) and ( 2 / 3 mathrm{cm} ). The size of the
object in cm is then
( A cdot 9 )
B. 4
( c cdot 3 )
D.
12
731A small piece of wire bent into L shape such that the upright and horizontal portions are of equal length. It is placed with the horizontal portion along the
axis of concave mirror of radius of
curvature ( 20 mathrm{cm} ). If the bend is ( 40 mathrm{cm} ) from the pole of the mirror, then the ratio of the length of the images of the upright and horizontal portions of the wire is
A ( cdot 1: 9 )
в. 1: 3
( c cdot 3: )
( D cdot 2: )
12
732Which principle is the basis for the transmission of light through fiber optic cables even if the cable is bent?
A. Photoelectric effect
B. Uncertainty principle
c. Light diffraction
D. Light polarization
E. Total internal reflection
12
733A short linear object of length ( boldsymbol{I} ) lies
along the axis mirror of focal length ( boldsymbol{F} )
at a distance u form the of the mirror.
The size of the image is approximately equal to:
( ^{mathbf{A}} cdotleft(frac{u-f}{f}right)^{1 / 2} )
( ^{mathrm{B}} cdot_{I}left(frac{u-f}{f}right)^{2} )
( ^{mathrm{c}} cdotleft(frac{f}{u-f}right)^{1 / 2} )
D. ( _{I}left(frac{f}{u-f}right) )
12
734Lenses of power ( 3 D ) and ( -5 D ) are
combined to from a compound lens.An object is placed at a distance of ( 50 mathrm{cm} ) from this lens. The position of its image will be; –
( A cdot-10 mathrm{cm} )
( B .+10 mathrm{cm} )
( c .-25 mathrm{cm} )
( D cdot+25 mathrm{cm} )
12
735(a) Define the power of lens.
(b) Draw a ray diagram for formation of image of an object situated at a point in
between ( 2 f_{1} ) and ( f_{1} ) distances from the optical centre of the concave lens and write the nature of the image formed.
(c) What happens when light is falling perpendicular to an interface of two media?
12
73646. An object is kept at a distance of 16 cm from a thin lens
and the image formed is real. If the object is kept at a
distance of 6 cm from the same lens, the image formed is
virtual. If the sizes, of the images formed are equal, the
focal length of the lens will be
(a) 15 cm
(b) 17 cm
(c) 21 cm
(d) 11 cm
12
737State whether the given statement is True or False.

An eye is said to be long-sighted, if the image of a distant object is formed in front of retina.

12
738If the wavelength of light is ( 4000 A ), then the number of waves in 1 mm length
will be
A . 2500
B . 25
( c .250 )
D. 25000
12
739Name the two major defects of an eye.
Explain causes of their development
and discuss methods of their
correction.
12
740How should people wearing spectacles
work with a microscope?
A. They should keep on wearing their spectacles
B. They should never use the microscope
C. They should take off their spectacles
D. They may either put on their spectacles or they may take off their spectacles
12
741A man can see objects clearly up to ( 3 m ) What type of lens he should use in order
to see clearly up to ( 12 m ? )
A. Convex lens, ( f=4 m )
B. Concave lens, ( f=4 m )
c. convex lens, ( f=-4 m )
D. Concave lens, ( f=-4 m )
12
742A small pin fixed on a table top is
viewed from above from a distance of
( 50 mathrm{cm} . ) By what distance would the pin
appear to be raised if it is viewed from
the same point through a ( 15 mathrm{cm} ) thick glass slab held parallel to the table?
Refractive index of glass ( =1.5 . ) Does the answer depend on the location of the
slab?
12
743Assertion
The maximum refractive index of liquid for total internal reflection of the ray
passing through the prism should be ( sqrt{2} )
Reason
Here critical angle is ( 45^{circ} )
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
744Which surfaces are said to be smooth?
A. As long as the irregularities of surfaces are small as compared to the wavelength of the incident light.
B. As long as surface irregularities are large compared to the wavelength of the incident light
C. As long as surface smoothness are small as compared to wavelength of reflected light
D. As long as the surface irregularities are large as compared to the wavelength of reflected light.
12
745thickness and refractive index ( n_{1}=1.4 )
is coated on the convex spherical
surface of radius ( R ) at one end of a long
solid glass cylinder of refractive index
( boldsymbol{n}_{2}=1.5, ) as shown in the figure. Rays of
light parallel to the axis of the cylinder
traversing through the film from air to
glass get focused at distance ( f_{1} ) from
the film, while rays of light traversing from glass to air get focused at
distance ( f_{2} ) from the film. Then
This question has multiple correct options
( mathbf{A} cdotleft|f_{1}right|=3 R )
B . ( left|f_{1}right|=2.8 R )
( mathbf{c} cdotleft|f_{2}right|=2 R )
D cdot ( left|f_{2}right|=1.4 R )
12
746A fish looks upward at an unobstructed
overcast sky. What total angle does the sky appear to subtend? (Take refractive index of water as ( sqrt{2} ) ).
( mathbf{A} cdot 180 )
B. 90
( c cdot 75 )
D. ( 60^{circ} )
12
747The far point of a myopic person is 40 cm. To see the distant objects clearly, the focal length and the power of the
lens used should be:
A. ( -40 mathrm{cm},-2.5 mathrm{D} )
B. ( -25 mathrm{cm},-4.0 mathrm{D} )
( c cdot+40 mathrm{cm},+2.5 mathrm{D} )
D. ( -40 mathrm{cm},+2.5 mathrm{D} )
12
748Braille writer slate and stylus is a type
of resource for blind people that is called tactual aid
A. True
B. False
12
749The velocity of electromagnetic radiation in a medium of permittivity ( varepsilon_{0} )
and permeability ( mu_{0} ) is given by :
A ( cdot sqrt{frac{varepsilon_{0}}{mu_{0}}} )
B . ( sqrt{mu_{0} varepsilon_{0}} )
c. ( frac{1}{sqrt{mu_{0} varepsilon_{0}}} )
D. ( sqrt{frac{mu_{0}}{varepsilon_{0}}} )
12
750If we want to see our full image then the minim um size of the plane mirror
A. Should be twice of our height
B. Should be of our height
c. should be half of our height
D. Depends upon our distance from mirror
12
751Distance between focus and optical centre of a lens is called
A. Focal plane
B. Focal length
c. Focus
D. Principal axis
12
752decomposes white light
into its constituent colors.
A. Flat glass slab
B. Convex mirror
c. Concave mirror
D. Prism
12
753A convex lens of focal length ( 0.2 mathrm{m} ) and
made of glass ( left(^{a} mu_{g}=1.5right) ) is immersed
in water ( left(^{a} mu_{w}=1.33right) . ) Find the change in the focal length of the lens.
( A cdot 5.8 mathrm{m} )
B. 158 m
c. ( 0.58 mathrm{m} )
D. ( 5.8 mathrm{cm} )
12
754What is the angle of deviation produced
by a glass slab? Explain with ray diagram.
12
75578. A ray of light enters a rectangular glass slab of refractive
index V3 at an angle of incidence 60°. It travels a distance
of 5 cm inside the slab and emerges out of the slab. The
perpendicular distance between the incident and the
emergent rays is
(a) 513 cm
(b) 5 cm
(c) 563/2 cm
(d) 5 cm
12
756Four rays, 1,2,3 and 4 are incident normally on the face ( P Q ) of an isosceles
prism PQR with apex angles ( angle Q=120^{circ} )
The refractive indices of the material of
the prism for the above rays 1,2,3 and 4 are 1.85,1.96,2.05 and ( 2.15, ) respectively and the surrounding medium is air. Then the rays emerging from the face QR are :
A. 4 only
B. 1 and 2 only
c. 3 and 4 only
D. 1,2,3 and 4
12
757A ray of light passes from glass, having
a refractive index of ( 1.6, ) to air. The angle of incidence for which the angle of refraction is twice the angle of incidence is
A ( cdot sin ^{-1}left(frac{4}{5}right) )
в. ( sin ^{-1}left(frac{3}{5}right) )
( ^{mathbf{c}} cdot sin ^{-1}left(frac{5}{8}right) )
D. ( sin ^{-1}left(frac{2}{5}right) )
12
758What type of lens from the following would you have in your magnifying lens to read a page in small print?
A. A convex lens of focal length ( 80 mathrm{cm} )
B. A concave lens of focal length 80 cm
c. A concave lens of focal length ( 4 mathrm{cm} )
D. A convex lens of focal length of ( 4 mathrm{cm} )
12
759Which of the following is responsible for glittering of diamond.
A . Interference
B. Diffraction
c. Total internal reflation
D. Refraction
12
760Two plane mirrors are inclined to each
other at an angle ( theta . ) A ray of light is reflected first at one mirror and then at
the other. The total deviation of the ray
is
A ( cdot 360^{circ}-2 theta )
B. ( 240^{circ}-20 )
c. 20
D. ( 180^{circ}-theta )
12
761The adjoining figures represent three cases of a ray passing through a prism of an angle ( A ). Which of the following figure represents the minimum deviation condition
A.
B. 2
( c .3 )
D. None of these
12
762State whether true or false:
The deviation produced by a prism is independent of the angle of incidence and is same for all the colours of light.
A . True
B. False
12
763A compound microscope has an objective of focal length ( 4 mathrm{mm} ) and an eyepiece of focal length ( 25 mathrm{mm} ). The objective produces a real image at a distance of ( 180 mathrm{mm} ). If the eye-piece is in normal adjustment, then the magnification is
A . 45
B. 90
( c cdot 225 )
D. 440
12
764Due to refraction, sunrise appears
sun comes to horizon and
sunset appears sun leaves
horizon respectively.
A. before, after
B. after, before
c. before, before
D. after, after
12
765Give reasons.
In old age bifocal lens is necessary
for person.
12
766Assertion
Optical fibres are used for
telecommunication.
Reason
Optical fibres are based on the
phenomenon of total internal reflection.
A. Both Assertion and Reason are correct and Reason is
the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
767Calculate the critical angle between glass and air. (Given ( left._{a} mu_{g}=frac{3}{2}right) )
A . 41.8
в. 45.8
c. 45
D. 30
12
768Assertion
If light enters from medium- 1 into
medium-2 and bends towards the
normal, its wavelength in medium-2 is smaller than its wavelength in medium-
1
Reason
According to Cauchy’s relation, ( mu= ) ( A+frac{B}{lambda^{2}} )
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
769A microscope has an objective of focal
length ( 1.5 mathrm{cm} ) and eye piece of focal
length ( 2.5 mathrm{cm} . ) If the distance between
objective and eye-piece is ( 25 mathrm{cm} ). What is the approximate value of magnification produced for relaxed
eye?
[Disclaimer: Option A is changed from
( mathbf{7 5} ) to ( mathbf{1 8 3 . 3 3} ) as the correct answer is
183.33 which is not present in the given options.]
A . 183.33
B. 110
c. 140
D. 25
12
770A reflecting surface is curved inwards. Now, the mirror formed is :
A. Concave
B. convex
c. Plane
D. None of these
12
77133. A plastic hemisphere has a
radius of curvature of 8 cm and
an index of refraction of 1.6. On
8 cm
the axis halfway between the
plane surface and the spherical
4 cm
one (4 cm from each) is a small
object O.
The distance between the two images when viewed
along the axis from the two sides of the hemisphere is
approximately
(a) 1.0 cm
mit (b) 1.5 cm
(c) 3.75 cm
(d) 2.5 cm
12
772A glass prism with a refracting angle
of ( 60^{0} ) has a refractive index 1.52 for red
and 1.6 for voilet light.A parallel beam of white light is incident on one face at an angle of incidence, which gives minimum deviation for red light. Find:
( left[boldsymbol{U} boldsymbol{s} boldsymbol{e}: sin left(mathbf{5 0}^{0}right)=mathbf{0 . 7 6 0} ; sin left(mathbf{3 1 . 6}^{mathbf{0}}right)=mathbf{0}right. )
2.The angular width of the spectrum is;
A ( .6^{circ} )
B . ( 4.8^{circ} )
c ( cdot 9.6^{circ} )
D. ( 12^{circ} )
12
773A convex mirror has a focal length ( f . mathbf{A} )
real object is placed at a distance ( f ) in front of it from the pole, produces an
image at:
( A cdot infty )
B. ( f )
( c cdot frac{f}{2} )
D. ( 2 f )
12
774The light which refracts most while
passing through a prism is
A . Red
B. Violet
c. Indigo
D. Yellow
12
775A point ‘ ( O^{prime} ) marked on the surface of a
glass sphere of diameter ( 20 mathrm{cm} ) is
viewed through glass from the position
directly opposite to the point ‘ ( O ) ‘. If the
refractive index of the glass is ( 1.5, ) find the position of the image formed. Also, draw the ray diagram for the formation
of the image.
12
776State two uses of : Irregular reflection12
777The power of plane mirror is
( mathbf{A} cdot mathbf{0} )
B . ( infty )
( c .2 D )
D. ( 4 D )
12
778In lateral inversion.
A. Right side of the object will be right side of the image
B. Left side of the object will be left side of the image
C. Upside of the object will be down side of the object
D. Right side of the object will be left side of the image
12
779A lens of glass is immersed in water.
What will be its effect on the power of
the lens?
12
780Find the power (with sign) of a concave lens of focal length ( 20 mathrm{cm} )
A . ( -4 D )
в. ( -5 D )
( c .4 D )
D. ( 5 D )
12
781The frequency of a light wave in a material is ( 2 times 10^{14} H z ) and wavelength is 5000 A. The refractive index of
material will be :
A . 1.50
B. 3.00
( c .1 .33 )
D. 1.40
12
782Light falls from glass to air. Find the angle of incidence for which the angle of
deviation is ( 90^{circ} . ) If refractive index of
glass is ( sqrt{2} )
12
783We want a mirror that will make an
object look larger. What combination of image and object distances (from the
mirror) will accomplish this?
A. Image Distance ( 3.0 mathrm{cm} ), Object Distance ( 3.0 mathrm{cm} )
B. Image Distance ( 2.0 mathrm{cm} ), Object Distance ( 3.0 mathrm{cm} )
C. Image Distance ( 3.0 mathrm{cm} ), Object Distance ( 5.0 mathrm{cm} )
D. Image Distance ( 3.0 mathrm{cm} ), Object Distance ( 2.0 mathrm{cm} )
E. Image Distance ( 3.0 mathrm{cm}, ) Object Distance ( 10.0 mathrm{cm} )
12
784A beam of light consisting of red, green and blue is incident on a right angled prism. The refractive index of the material of the prism for the above red, green and blue wavelengths are 1.39 1.44 and 1.47 respectively. The prism will
A. separate part of the red color from the green and blue colors
B. separate part of the blue color from the red and green colors
c. Separate all the three colors from the other two colors
D. not separate even partially any color from the other two colors
12
785Which part of the eye is a dark muscular diaphragm?
A. Iriss
B. Cornea
c. Pupil
D. Retina
12
786For paraxial rays, show that the focal length of a spherical mirror is one-half
of its radius of curvature.
12
787a distance ( L ) in front of the centre of a
mirror of width ( d ), hung vertically on a
wall. A man walks in front of the mirror
along a line parallel to the mirror at a
distance ( 2 L ) from it as shown in the
figure. The greatest distance over which
he can see the image of the light source
in the mirror is :
( mathbf{A} cdot d / 2 )
B. ( d )
c. ( 2 d )
D. ( 3 d )
12
78882. A hollow double concave lens is made of very thin
transparent material. It can be filled with air or either of
two liquids L, or L, having refractive indices n, and n2,
respectively (n2>n, > 1). The lens will diverge parallel
beam of light if it is filled with
(a) air and placed in air (b) air and immersed in Li
(c) L, and immersed in L2 (d) L and immersed in L
12
789The electromagnetic waves travel with a velocity
A. equal to velocity of sound.
B. equal to velocity of light
c. less than velocity of light
D. None of the above
12
790( fleft(mu_{0}=sqrt{2} ) and the rayjust fail to right.
emerge from the prism, refractive index
( mu ) of the solid will be
( A cdot 1.2 )
B. ( sqrt{2} )
( c )
D. ( sqrt{3} / 2 )
12
791The equiconvex lens has focal length ‘f. If it is cut perpendicular to the principal axis passing through optical centre,
then focal length of each half is :
A ( cdot frac{f}{2} )
B. ( f )
( c cdot frac{3 f}{2} )
D. ( 2 f )
12
792The type of lens present in human eye is
A. Convex lens
B. Concave lens
c. Plano convex lens
D. Plano concave lens
12
7931
.
18. The image of an object placed on the principal axis of a
concave mirror of focal length 12 cm is formed at a point
which is 10 cm more distance from the mirror than the
object. The magnification of the image is
(a) 8/3 centro. (b) 2.5
(c) 2
(d) -1.5
12
794A ray of light is incident on a plane
mirror and the angle of reflection is ( 50^{circ} )
Calculate the angle between the incident ray and the reflected ray.
A ( .50^{circ} )
B . ( 25^{circ} )
( c cdot 90^{circ} )
D. ( 100^{circ} )
12
795The focal lengths of the objective and eyepiece of a compound microscope are ( 2 mathrm{cm} ) and ( 3 mathrm{cm} ) respectively. The distance between the objective and eyepiece is ( 15 mathrm{cm} . ) The final image formed is at infinity. The distances in cm of object and image from objective are going to be then:
( A cdot 2.4 ) and 12
B. 2.4 and 15
c. 2.3 and 3.0
D. 2.3 and 12
12
796The plane of a mirror makes an angle
( 30^{circ} ) with borizontal. If any vertical ray is incident on the mirror, then angle made by the reflected ray on plane mirror will be-
( A cdot 30 )
B . 45
( c cdot 60 )
D. ( 90^{circ} )
12
797The centre of curvature of a ….. mirror is
behind it.
A. convex
B. Concave
c. convex or concave
D. None of these
12
798The wavelength and frequency of beam of light in water of refractive index ( 4 / 3 ) having wavelength 0.48 micron in air
are
A. ( 0.16 times 10^{-6} m, 6.25 times 10^{14} H z )
В. ( 0.36 times 10^{-6} m, 6.25 times 10^{14} H z )
c. ( 0.36 times 10^{-6} m, 3.25 times 10^{14} H z )
D. ( 0.26 times 10^{-6} m, 6.25 times 10^{14} H z )
12
799Which of the following occurs when light is reflected from a smooth flat
glass surface, as shown above?
A. The light is somewhat intensified
B. The light is somewhat polarized
C. The light is focused
D. The velocity of the light is reduced
E. The color of the light is shifted toward the blue end of the spectrum.
12
800A boy rotates his arm in clockwise
direction in front of mirror. His mirror
image rotates its arm in:
A. anticlockwise direction
B. clockwise direction
c. oscillatory motion
D. insufficient info
12
801A parallel beam of light is incident from
air at an angular ( alpha ) on the side PQ of a right – angled triangular prism of refractive index ( n=sqrt{2} )
Light undergoes total internal reflection
in the prism at the face PR when ( alpha ) has
a minimum value of ( 45^{circ} . ) The angle ( theta ) of
the prism is
A ( cdot 15^{circ} )
В ( cdot 22.5^{circ} )
( c cdot 30^{circ} )
D. ( 45^{circ} )
12
802The figure shows a mixture of blue,
green and red colour ray incident on the right angled prism. The critical angles
of the material of prism for red, green
and blue colours are ( 46^{circ}, 44^{circ} ) and ( 43^{circ} )
respectively. The arrangement will
separate:
A. red colour from green and blue
B. blue colour from green and red
c. green colour from red and blue
D. all the three colours
12
803ABC represents the principal cross-
section of an equilateral prism made
with a transparent material. If PQRS
indicates the path of a light ray, find the refractive index of the material.
A ( cdot frac{1}{sqrt{2}} )
B. ( frac{2}{sqrt{3}} )
( c cdot sqrt{2} )
D. ( frac{sqrt{3}}{2} )
12
804Draw a labelled diagram to show
( (i) )
reddish appearance of the sun at the
sunrise or the sunset
12
805A ray of light incident parallel to the base PQ of an isosceles right-angled
triangular prism PQR suffers two
successive total internal reflections at
the faces ( mathrm{PQ} ) and ( mathrm{QR} ) before reversed in
direction as shown. If the
refractive index of the material of the
prism is ( mu, ) then find the value of ( mu )
12
806Any ray which passes through the point is not deviated by the lens.
4
( B )
( c .2 )
Don
12
807Resolving limit of a healthy eye is12
808A convex lens has focal length ( 30 mathrm{cm} ). If an object is placed at a distance of 15 ( mathrm{cm} ) from it then the magnification produced by the lens is?
A . 6.66
B. 0.5
c. 1
( D )
12
809A ray of light is incident on glass slab making an angle of incidence ( sin ^{-1}left(frac{sqrt{3}}{2}right) . ) What will be the angle of
refraction in glass of refractive index
1.5?
( mathbf{A} cdot 40^{circ} 18 )
В ( cdot 24^{circ} 49^{prime} )
c. ( 25^{circ} ) о ( 7^{text {। }} )
( mathbf{D} cdot 35^{circ} 16^{prime} )
12
810A ray of light is incident normally on one
face of a ( 30^{circ}-60^{circ}-90^{circ} ) prism of
refractive index ( frac{mathrm{t}}{text { imersed in water of }} ) ( mathbf{Z} )
refractive index ( frac{-}{2} ) as shown ( overline{mathbf{3}} )
This question has multiple correct options
A ( cdot ) the exit angle ( theta_{2} ) of the ray is ( sin ^{-1}left(frac{5}{8}right) )
B ( cdot ) the exit angle ( theta_{2} ) of the the ray is ( sin ^{-1}left(frac{5}{4 sqrt{3}}right) )
C. total internal reflection at point P ceases if the
refractive index of water is increased to ( frac{5}{2 sqrt{3}} ) by
dissolving some substance
D. Total internal reflection at point P ceases if the
refractive index of water is increased to ( frac{-b y}{y} )
dissolving some substance.
12
811Refraction of light in the eye occurs at
A. The pupil only
B. The cornea only
c. The lens only
D. Both the cornea and the lens
12
812The plane side of a thin plano-convex
lens with radius of curvature ( 20 mathrm{cm} ) is
silvered to obtain a concave mirror. An
object is located at a distance of ( 25 mathrm{cm} ) in front of this mirror. The distance of
the image from the mirror is ( (mu=1.5) )
A . ( 100 mathrm{cm} )
в. ( frac{100}{11} mathrm{cm} )
( c cdot 6.25 c m )
D. ( frac{100}{9} mathrm{cm} )
12
813A simple microscope consists of a concave lens of power ( 10 mathrm{D} ) and a convex lens of power 15 D. Its magnification at
near point is (least distance of distinct vision, ( mathrm{D}= )
( 25 mathrm{cm} )
A . 2.25
B. 5
( c cdot 10 )
D. 20
12
814A water drop in air reflects the light rays
as
( A )
в.
( c )
( D )
12
815Derive an expression for the refractive index of the material of a prism.12
816A thin prism of angle ( 5^{circ} ) is placed at a
distance of ( 10 mathrm{cm} ) from object. What is the distance of the image from object?
(Given ( mu ) of prism ( =1.5 ) )
A ( cdot frac{pi}{8} c m )
в. ( frac{pi}{12} mathrm{cm} )
c. ( frac{5 pi}{36} c m )
D. ( frac{pi}{7} c m )
12
817Differentiate between regular and
irregular reflection.
12
818What is the ability of the eye lens to
adjust its focal length called?
12
819The splitting of white light into constituent colors is called12
820A thin prism of angle ( 15^{circ} ) made of glass
of refractive index ( mu_{1}=1.5 ) is combined
with another prism of glass of refractive
index ( mu_{2}=1.75 . ) The combination of the
prism produced dispersion without deviation. The angle of the second prism
should be :
A ( cdot 5^{circ} )
B . ( 7^{circ} )
( c cdot 10^{circ} )
D. ( 12^{circ} )
12
821A student uses a converging lens to produce an enlarged virtual image of a scale she wishes to read accurately. The
focal length of the lens is ( 10 mathrm{cm} ). What
is a suitable distance between the scale
and the lens?
( A cdot 8 c m )
B. ( 10 mathrm{cm} )
( mathrm{c} cdot 15 mathrm{cm} )
D. ( 20 mathrm{cm} )
12
822An object, ( 1 m ) tall, is put in front of a
plane mirror at a distance of 0.2 m.The
size of the image formed is:
A. ( 0.2 m )
в. ( 0.5 m )
( mathrm{c} .0 .1 mathrm{m} )
D. ( 1 m )
12
823Laws of reflection hold good for
A. Plane mirrors
B. Concave mirrors
c. Convex mirrors
D. All
12
824In snells law ( mu_{1} sin theta_{1}=mu_{2} sin theta_{2} )
Type 1 for true and 0 for flase
12
825An electromagnetic wave of frequency
( boldsymbol{v}=mathbf{3 . 0} boldsymbol{M} boldsymbol{H} boldsymbol{z} ) passes from vacuum
into a dielectric medium with
permittivity ( epsilon=4.0 . ) Then
A. wavelength is halved and frequency remains unchanged.
B. wavelength is doubled and frequency becomes half.
C. wavelength is doubled and frequency remains unchanged.
D. wavelength and frequency both remain unchanged.
12
826The path of beam of light becomes in a colloidal solution.
A . visible
B. invisible
c. white
D. dispersed
12
827The magnification produced by a plane mirror is ( +1 . ) What does this mean?12
828Which of the following phenomenon has two angles that are equal to each other?
A. Reflection
B. Refraction
c. Diffraction
D. constructive interference
E. Destructive interference
12
829If the focal length of a lens is ( 50 mathrm{cm} ), its power would be
A. 50 dioptres
B. 2 dioptres
c. 20 dioptres
D. 0.5 dioptres
12
830What is reflection? Give two examples.12
831The figure above shows the eye
suffering from:
A. hypermetropia
B. myopia
C . astigmatism
D. far-sightedness
12
832By which optical phenomena the splitting of white light into seven
constituent colours occur?
A. Refraction
B. Dispersion
c. Reflection
D. Interference
12
833Read the given statements and select
the correct option.

Statement 1: Rahul placed a coloured plastic bottle in front of the beam of a
torch light. Then he placed a transparent sheet of same size on the
other side of bottle. No shadow will form
on the screen.

Statement 2: Translucent objects allow
light to pass through them partially.
A. Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1.
B. Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1 .
c. Statement 1 is true but statement 2 is false.
D. Statement 1 is false but statement 2 is true

12
834Assertion: In optical fibre, the diameter of the core is kept small.

Reason: This smaller diameter of the
core ensures that the fibre should have incident angle more than the critical angle required for total internal reflection.
A. Both assertion and reason are true but the reason is the correct explanation of assertion
B. Both assertion and reason are true but the reason is not the correct explanation of assertion
c. Assertion is true but reason is false
D. Both the assertion and reason are false
E. Reason is true but assertion is false

12
835You are standing upright in a room in front of a vertical mirror. In this mirror,
you can see from your position, only the upper two- third part of your body. You
wish to see the full image of your body
in the mirror. Which combination of the
following three courses of action will achieve this? I. Move away from the mirror II. Move towards the mirror III.
Use a mirror whose height will allow you
to see your full image
A. I only
B. II only
c. III only
D. Either I or III
12
836According to the laws of reflection,
angle of incidence is equal to angle of reflection
A. True
B. False
12
837Inability of the eye to focus on both far and near objects with advancing age is:
A. Astigmatism
B. Presbyopia
c. Myopia
D. Hypermetropia
12
838What is lens ( B ) called?
Parallel
point of distant
12
839A ray of light travelling in air enters
obliquely into water. Does the light ray
bend towards the normal or away from the normal?
12
840A straight line graph is obtained by plotting sine of angle of incidence versus sine of angle of refraction. The slope of this graph represents:
A. Velocity of light
B. Refractive index
c. Gravitational
D. None of these
12
841You are given prisms made of crown glass and flint glass with a wide variety of angles. Suggest a combination of prisms which will
(a) deviate a pencil of white light without much dispersion,
(b) disperse (and displace) a pencil of white light without much deviation.
12
842Light in air is incident at an angle of ( 45^{circ} )
on the surface of glass plate having Refractive index 1.526 through what angle is light deviated upon refraction at top of surface.
12
843The focal length of a glass slab of
refractive index 1.5 is
A . Infinite
B. Zero
c. Unity
D. None of these
12
844A prism of refractive index ( sqrt{2} ) has
refracting angle ( 60^{0} ). Angle of minimum
deviation is:
A ( cdot 45^{circ} )
В. ( 90^{circ} )
( c cdot 30^{0} )
D. none
12
845A double convex lens made of glass has
both radii of curvature of magnitude 20
cm. Incident light rays parallel to the axis of the lens will converge at a distance at [Given refractive index of glass ( =1.5] )
A . 20
B. 10
( c cdot 40 )
D. ( frac{40}{3} )
12
846A point source of light is moving at a rate of ( 2 mathrm{cm}-s^{-1} ) towards a thin
convex lens of focal length ( 10 mathrm{cm} ) along
its optical axis. When the source is
( 15 c m ) away from the lens the image is
moving at
A ( cdot 4 mathrm{cm}-s^{-1} ) towards the lens
B. ( 8 mathrm{cm}-s^{-1} ) towards the lens
C. ( 4 mathrm{cm}-s^{-1} ) away from the lens
D. ( 8 mathrm{cm}-s^{-1} ) away from the lens
12
847What is meant by refraction of light? State the laws of refraction.12
848What gives a perception of depth or three dimensional vision to human eye?12
849An object ( 2.5 mathrm{cm} ) high is placed at a
distance of ( 10 mathrm{cm} ) from a concave
mirror of radius of curvature ( 30 mathrm{cm} . ) The
size of the image is:
( mathbf{A} cdot 9.2 mathrm{cm} )
в. ( 10.5 mathrm{cm} )
c. ( 5.6 mathrm{cm} )
D. ( 7.5 mathrm{cm} )
12
850Long-sightedness is to hypermetropia as short-sightedness is to :
A. myopia
B. focusing
c. astigmatism
D. accomodation
12
851Which of the following phenomena cannot be explained by scattering of light ?
A. Blue colour of sky
B. Colour of clouds
c. Tyndall effect
D. Formation of rainbow
12
852A thin plano convex lens of focal length
( f, ) is split into two halves. One of the halves is shifted along the principal
axis as shown. The separation between
an object placed on the axis and its
image is ( 1.8 m )
The magnification of the image formed
by one of the half lenses is 2 . Find the
focal length of the combination and the separation between the two halves.
( A cdot 0.4 m )
B. ( 0.5 mathrm{m} )
c. ( 0.6 mathrm{m} )
D. ( 0.7 mathrm{m} )
12
853A biconvex lens made of a transparent material of refractive index 1.25 is
immersed in water of refractive index
1.33. Will the lens behave as a
converging or a diverging lens? Give
reason.
12
854A ray of light travels from a denser to a rarer medium then, the ray:
A. doesn’t bend at all
B. bends towards the normal
c. bends away from the normal
D. goes along the normal
12
855Answer the question in the limit of
maximum 50 words.
Describe the dispersion of light by glass prism with neat figure.
12
856A double convex lens is made of glass which has refractive index 1.55 for violet
rays and 1.50 for red rays. If the focal length of violet rays is ( 20 mathrm{cm}, ) the focal length for red rays is :
A. ( 9 mathrm{cm} )
B. ( 18 mathrm{cm} )
c. ( 20 mathrm{cm} )
D. 22 cm
12
857If the angle of incidence is ( 70^{circ}, ) then
calculate the angle between the incidence ray and the reflected ray.
A ( .50^{circ} )
B . ( 140^{circ} )
( mathrm{c} cdot 130^{circ} )
D. ( 80^{circ} )
12
858A point source of light is placed at the
bottom of a water lake. If the area of the
illuminated circle on the surface is
equal to 3 times the square of the lake. The refractive index of water is
A. ( sqrt{pi+1} )
B. ( sqrt{frac{pi}{3}+1} )
c. ( frac{pi}{3}+1 )
D. ( frac{pi}{4}+1 )
12
859Which of the following is true for
cornea?
A. It allows light to enter the eye
B. Most of the refraction of light occurs on the outer surface of cornea
C. It forms a transparent bulge on the outer surface of the eyeball.
D. All of the above
12
860Draw the diagram that explains the formation of an image by a plane mirror.12
861Read the statements and mark the
correct one:
i. It has 63 dot patterns or characters.
ii. through Braille system,visually challenged people can only read the languages.
iii. It is a coded language based on logical system
B. i, ii
c. ii, ii
D. All are true
12
862A bulb is located on a wall. Its image is to be obtained on a parallel wall with the help of convex lens. If the distance
between parallel walls and lens is ( ^{prime} d^{prime} ) then, required focal length of lens placed in between the walls is:
A ( cdot ) only ( frac{d}{4} )
B. only ( frac{d}{2} )
c. More than ( frac{d}{4} ) but less than ( frac{d}{2} )
D. Less than or equal to ( frac{d}{4} )
12
863Two thin lenses of powers ( 2 D ) and ( 3 D ) are placed in contact. An object is placed at a distance of ( 30 mathrm{cm} ) from the combination. The distance (in cm) of
the image from the combination is :
A . 30
B. 40
( c .50 )
D. 60
12
864Which of the following statement is
correct?
A. A person with myopia can see distant objects clearly
B. A person with hypermetropia can see nearby objects clearly
C. A person with myopia can see nearby objects clearly
D. A person with hypermetropia cannot see distant objects clearly
12
865( frac{sqrt{x}}{frac{x}{x}} )12
866A point object is placed at a distance of ( 12 mathrm{cm} ) on the axis of a convex lens of
focal length ( 10 mathrm{cm} . ) On the other side of the lens, a convex mirror is placed at a distance of ( 10 mathrm{cm} ) from the lens such that the image formed by the combination coincides with the object
itself. The focal length of the convex
mirror is
( A cdot 20 mathrm{cm} )
B. 25 cm
( c . ) 30 ( mathrm{cm} )
D. 22 cm
12
867Assertion
Although the surface of goggles’ lens is curved, it does not have any optical
power.
Reason
In case of goggles, both the curved surfaces have equal radii of curvature
and have centre of curvature on the
same side.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
868Two lenses of power ( 10 D ) and ( -10 D ) are in contact, find power, focal length and nature of lens combination.12
869When the plane surface of a planoconvex lens of refractive index 1.5 is
silvered, it behaves like a concave mirror with ( boldsymbol{f}=mathbf{3 0} ) cm.When its convex
surface is silvered, it will behave like a
concave mirror of focal length:
( mathbf{A} cdot 10 mathrm{cm} )
B. ( 20 mathrm{cm} )
c. ( 30 mathrm{cm} )
D. ( 45 mathrm{cm} )
12
870Cataract is a condition of eye when:
A. eye sight becomes foggy
B. eye lens becomes cloudy
C. there is a loss of vision
D. all of the above
12
871In the absence of atmosphere, the sky
appears:
A . coloured
B. blue
c. indigo
D. black
12
872The sum of the reciprocals of object distance and image distance is equal to the of a mirror.
A. focal length
B. reciprocal of the focal length
c. radius of curvature
D. reciprocal of the radius of curvature
12
873Larger particles scatter light at the end of the spectrum the least.
A. Blue
B. Green
c. violet
D. Red
12
874An object ( 10 mathrm{cm} ) from lens, has a virtual image at ( 10 mathrm{cm} ) from the object. The power of the lens is
A. 10 diopters
B. -10 diopters
c. 5 diopters
D. – diopters
12
875Which of the following describes an object that allows no light to pass through it?
A. Transparent
в. ०раяче
c. Translucent
D. Diffuse
12
876Fill in the blanks:
An aged person suffering from caused by the weak accommodation power of the eye lens associated with old age, should wear
lenses.
A. Myopia, concave
B. Hypermetropia, convex
c. Presbypoia, bifocal
D. Astigmastism, cylindrical
12
877A convex lens forms an image of an object on a screen. The height of the image is ( 9 mathrm{cm} . ) The lens is now displaced until an image is again obtained on the screen. The height of this image is ( 4 mathrm{cm} . ) The distance
between the object and the screen is 90
( mathrm{cm} )
A. The distance between the two positions of the lens is 30 ( mathrm{cm} )
B. The distance of the object from the lens in its first position is 36 ( mathrm{cm} )
c. The height of the object is ( 6 mathrm{cm} )
D. The focal length of the lens is 21.6 ( mathrm{cm} )
12
878A ray of light traveling in water is
incident on its surface open to the air.
The angle of incidence is ( theta, ) which is
less than the critical angle. Then there
will be
A. Only a reflected ray and no refracted ray
B. Only a refracted ray and no reflected ray
C. A reflected ray and a refracted ray and the angle between them would be less than ( 180^{circ}-2 theta )
D. A reflected ray and a refracted ray and the angle between them would be greater than ( 180^{circ}-2 theta )
12
879State Snells law.
Calculate the velocity of light in a glass block of refractive index 1.5
(Velocity of light in air ( left.=3 times 10^{8} m s^{-1}right) )
12
880Fill in the blanks:
The reflecting surface of a spherical mirror may be curved
12
881When an equiconvex lens ( left(mu_{text {lens}}=mathbf{1 . 5}right) )
is placed over a plane mirror as shown,
then object needle and its image coincide at ( 15 mathrm{cm} . ) When a liquid of
refractive index ( mu ) is filled in the gap
between mirror and lens, the object
needle and its image coincide at ( 40 mathrm{cm} )
Find the refractive index ( mu ) of the liquid.
( A cdot 8 )
5
B. 5 8
( c cdot frac{13}{8} )
D. ( frac{5}{13} )
E ( cdot frac{13}{5} )
12
882The optical length of an astronomical telescope with magnifying power of 10 for normal vision is ( 44 mathrm{cm} . ) What is focal
length of the objective?
A. ( 40 mathrm{cm} )
B. 22cm
( c cdot 10 c m )
D. ( 4 mathrm{cm} )
12
883Assertion
Although the surfaces of goggle lenses are curved, it does not have any power
Reason
In case of goggle, both the curved surfaces have equal radii of curvature and have center of curvature on the
same side
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Assertion is incorrect but Reason is correct
12
884The angle between incident ray and
reflected ray is ( 60^{circ} . ) What is the value of
angle of incidence?
A ( .30^{circ} )
B. 60
( c cdot 120 )
D. None of the above
12
885Behind a thin converging lens having both the surfaces of the same radius
( mathbf{1} boldsymbol{c m}, ) a plane mirror has been placed. The image of an object at a distance of
( 40 mathrm{cm} ) from the lens is formed at the
same position. What is the refractive
index of the lens?
A . 1.5
B. ( 5 / 3 )
( c cdot 9 / 8 )
D. None of these
12
886State Snell’s law of refraction of light.12
887Study the following diagrams in which the path of a ray of light
passing through a glass prism as traced by four students ( P, Q, R ) and ( S ) is
shown. The student who has traced the
path correctly is :
( A )
B. ( Q )
( c . R )
( D )
12
888The amount of light reflected depends
upon
A. the nature of material of the object
B. the nature of the surface
c. the smoothness of the surface
D. all the above
12
889Rays of light are entering from glass to glycerine. If refractive indexes of glass and glycerine are respectively 1.5 and 1.47, find the refractive index of
glycerine with respect to glass.
A. 0.03
B. 1.02
( c cdot 2.20 )
D. 0.98
12
890If the angle of incidence is ( 80^{circ}, ) what will be the angle of reflection with respect to the normal drawn perpendicular at the point of reflection?
A . ( 80^{circ} )
B. ( 100^{circ} )
( c cdot 160^{circ} )
D. ( 20^{circ} )
12
891Draw a labelled ray diagram of a refractive telescope. Deduce an
expression of magnifiying power of it. Write two main limitations of a
refracting type telescope over a reflecting type telescope.
12
892Moon is visible to us because:
A. it reflects light
B. it refracts light
c. it emits light
D. it absorbs light
12
89319. A spherical mirror forms an image of magnification 3. The
object distance, if focal length of mirror is 24 cm, may be
(a) 32 cm, 24 cm (b) 32 cm , 16 cm
(c) 32 cm only
(d) 16 cm only
11.:. … edno v cm L
12
894Prisms are used in binoculars. Collect
information why prisms are used in
binoculars.
12
895A convex lens forms a real image of a point object placed on its principal axis. If the upper half of the lens is painted black
(i) The image will be shifted downward
( (i i) ) The image will be shifted upward
( (i i i) ) The image will not be shifted
( (i v) ) The intensity of the image will decrease
A. (i) and ( ( (i) ) )
B. (ii) and (iii)
c. ( (i i i) ) and ( (i v) )
D. only ( (i v) )
12
896There is a small black dot at the centre
C of a solid glass sphere of refractive index ( mu . ) When seen from outside, the
dot will appear to be located:
A. Away from C for all values of ( mu )
B. At C for all values of ( mu )
c. At ( mathrm{C} ) for ( mu=1.5 ), but away from ( mathrm{C} ) for ( mu neq 1.5 )
D. At C only for ( sqrt{2} leq mu leq 1.5 )
12
897The aperture diameter of a telescope is
5 ( m ). The separation between the moon and the earth is ( 4 times 10^{5} mathrm{km} . ) With light of wavelength of ( 5500 A ), the minimum separation between objects on the surface of moon, so that they are just
resolved, is close to?
A. ( 60 mathrm{m} )
в. 20
c. 600 m
D. 200 m
12
898A lens is placed between the source of light and a wall. It forms images of area
( A_{1} ) and ( A_{2} ) on the wall for its two different positions. The area of the source of light is :
в. ( frac{A_{1}+A_{2}}{2} )
( ^{mathrm{c}}left(frac{sqrt{A_{1}}+sqrt{A_{2}}}{2}right)^{2} )
D. None of these
12
899The relation between ( u, v ) and ( r ) is:
A ( cdot r=frac{2 u v}{u+v} )
B. ( r=frac{2}{u+v} )
c. ( r=frac{2(u+v)}{(u v)} )
D. None of these
12
900The retina is a delicate spot that
receives images through the eye lens and makes us see the world. If it gets
detatched, it is very difficult to join it back. Therefore, eye surgeons use
A. Laser-beams for welding the retina
B. Sound waves for joining
c. Micro-knives for surgery
D. Ultraviolet rays for surgery
12
901A real image ( , 4 / 5 ) times size of the object is formed ( 18 mathrm{cm} ) from a lens.
Calculate the focal length of the lens.
12
902The adjoining diagram shows the view
through the eyepiece of a prism
spectrometer with its slit illuminated
by the source of light emitting three wavelengths corresponding to yellow
(Y), Green (G) and unknown colour (X).
The colour at ( X ) may be:
( mathbf{A} cdot operatorname{Red} )
B. Orange
c. Pink
D. Blue
12
903An object placed at a distance of ( 16 mathrm{cm} ) from first principal focus of convex lens, produces a real image at a distance of ( 36 mathrm{cm} ) from its second principal focus
Then the focal length of the lens is :
( mathbf{A} cdot 9 c m )
B. ( 25 mathrm{cm} )
( mathbf{c} cdot 24 c m )
D. ( 17 mathrm{cm} )
12
904Which of the following foods are rich in Vitamin A?
A. Carrot
B. Cauliflower
c. Green Chillies
D. Beans
12
905A passenger in an aeroplane shall
A. never see a rainbow.
B. may see a primary and a secondary rainbow as concentric circles.
C. may see a primary and a secondary rainbow as concentric arcs.
D. shall never see a secondary rainbow.
12
906A person with myopic vision see objects only up to a distance of ( 0.25 mathrm{m} . ) To be able to read a book placed at the distance of ( 0.50 mathrm{m} ) from the eyes, the
spectacles needed by this person have
power of
A . -1.00
B . -1.5
c. – 2.0 ( D )
D. +2.00
12
907The human eye forms the image of an
object at its
12
908In
fig., ( L ) is a converging lens of focal length ( 10 c m ) and ( M ) is a concave mirror
of radius of curvature ( 20 mathrm{cm} . ) A point
object ( boldsymbol{O} ) is placed in front of the lens at
a distance of ( 15 mathrm{cm} . A B ) and ( C D ) are
optical axes of the lens and mirror, respectively. Find the distance of the final image formed by this system from the optical center of the lens. The distance between ( C D ) and ( A B ) is ( 1 c m ).
12
909When an object is placed ( 20 mathrm{cm} ) from a complex lens then a real image is formed ( 30 mathrm{cm} ) from the lens. Where
should the object be placed so that a real image of the same size is formed
by the lens.
A. object should be placed ( 24 mathrm{cm} ) from the lens.
B. object should be placed ( 34 mathrm{cm} ) from the lens.
c. object should be placed 14 cm from the lens.
D. object should be placed 30 cm from the lens
12
910Assertion
A convex lens of glass ( (mu=1.5) ) behave as a diverging lens when immersed in carbon disulphide of higher refractive index ( (mu=1.65) )
Reason
A diverging lens is thinner in the middle
and thicker at the edges.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
911Two thin similar convex glass pieces
are joined together front to front with its rear portion silvered such that a sharp
image is formed ( 20 mathrm{cm} ) from the mirror.
When the air between the glass pieces
is replaced by water ( left(mu_{W}=4 / 3right), ) then the image formed from the mirror is at
a distance of
( A cdot 8 mathrm{cm} )
B. ( 10 mathrm{cm} )
( c cdot 6 mathrm{cm} )
D. ( 12 mathrm{cm} )
12
912The angle of deviation by a prism is
( left(180^{circ}-2 Aright) . ) Its critical angle will be
A ( cdot sin ^{-1}left(tan frac{A}{2}right) )
B. ( left(cot frac{A}{2}right) )
c. ( cos ^{-1}left(cot frac{A}{2}right) )
D. ( cos ^{-1}left(tan frac{A}{2}right) )
12
913A convex lens ( (boldsymbol{f}=mathbf{2 0} boldsymbol{c m}) ) is placed at
( 80 mathrm{cm} ) from a concave mirror. An object
is placed at ( 30 mathrm{cm} ) in front the lens such
that position of its final image is same
or without the mirror. The maximum
distance of object and mirror for virtual image to be formed if only mirror is
present is:
A ( .10 mathrm{cm} )
B. ( 20 mathrm{cm} )
( c .30 mathrm{cm} )
D. ( 50 mathrm{cm} )
12
914When light rays enter the eye, most of the refraction occurs at the:
A. crystalline lens.
B. outer surface of the cornea
c. iris
D. pupil.
12
915When an object is placed at a distance of ( 60 mathrm{cm} ) rom a convex spherical mirror, the magnification produced is ( frac{1}{2} . ) Where should the object be placed to get a magnification of ( 1 / 3 )12
916A thin lens of focal length ( f ) and
aperture diameter ( d ) forms an image of intensity ( I . ) If the central part of the aperture upto diameter ( boldsymbol{d} / 2 ) is blocked by an opaque paper, then the new focal length and intensity of image will be
A ( cdot frac{f}{2}, frac{l}{2} )
B. ( frac{f}{2}, frac{3}{4} l )
( c cdot_{f, frac{1}{2}} )
D. ( f, frac{3}{4} l )
12
917What is the difference between concave
and convex mirrors? Choose the correct
statement?
A. Convex mirror is curved outwards and concave mirror is curved inwards
B. Focal point is in front of convex mirror and for a concave mirror, it is behind
c. centre of curvature is in front of convex mirror and for concave mirror, it is behind
D. None of these
12
918In the given figure a piano-concave lens is placed on a paper on which a flower is drawn. how far above its actual position
does the flower appear to be?
( A cdot 10 mathrm{cm} )
B. ( 15 mathrm{cm} )
( c cdot 50 mathrm{cm} )
D. none of these
12
919In the dispersion of white light from a prism, the violet light is deviated more
than the red light because:
A. Velocity of violet rays of light is more
B. Wavelength of violet rays of light is more
c. The frequency of violet rays of light is more
D. The refractive index of prism for violet rays of light is more
12
920If a newton’s colour disc composed of seven colours is rotated at high speed, it appears as
A. Seven coloured disc rotating
B. Few colours merge and only three dominant colours are visible
c. Colours mix and it appears white
D. colours mix giving a sparkling effect
12
921A convex refracting surface of radius of
curvature ( 20 mathrm{cm} ) separates two media of refractive indices ( 4 / 3 ) and ( 1.60 . ) An
object is placed in the first medium ( (mu=4 / 3) ) at a distance of ( 200 mathrm{cm} ) from
the refracting surface. The position of
the image formed is
A . ( 120 mathrm{cm} )
B. 240 cm
( c .100 mathrm{cm} )
D. 60 cm
12
922What length of the bottom ( A B ) the man
can see?
12
923The size of an object as perceived by an eye depends primarily on
A. Actual size of the object
B. Distance of the object from the eye
c. Aperture of the pupil
D. Size of the image formed on the retina
12
924Draw a ray diagram in each of the following cases to show the formation of image, when the object is placed:
(i) between optical centre and principal focus of a convex lens.
(ii) anywhere in front of a concave lens.
(iii) at ( 2 mathrm{F} ) of a convex lens.
State the signs and values of magnifications in the above mentioned cases (i) and (ii).
12
925What is meant by scattering of light? Use this phenomenon to explain why the clear sky appears blue or the Sun appears reddish at sunrise.12
926toppr
Q Type your question
at the eye by the virtual image produced by a magnifying glass. In what sense then does a magnifying glass provide angular magnification?
(b) In viewing through a magnifying glass, one usually positions ones eyes very close to the lens. Does angular
magnification change if the eye is
moved back?
(c) Magnifying power of a simple microscope is inversely proportional to the focal length of the lens. What then stops us from using a convex lens of
smaller and smaller focal length and achieving greater and greater magnifying power?
(d) Why must both the objective and the eyepiece of a compound microscope have short focal lengths?
(e) When viewing through a compound microscope, our eyes should be positioned not on the eyepiece but a short distance away from it for best viewing. Why? How much should be that short distance between the eye and eyepiece?
12
927In which of the following cases will there
be no dispersion when sunlight passes
( mathbf{A} )
B.
( c )
D.
12
928A planar structure of length L and width Wis made of two different optical
media of refractive indices ( n_{1}=1.5 )
and ( n_{2}=1.44 ) as shown in figure. If ( L> )
( >W, ) a ray entering from end ( A B ) will
emerge from end ( mathrm{CD} ) only if the total internal reflection condition is met
inside the structure. For ( boldsymbol{L}=mathbf{9 . 6 m}, ) if
the incident angle ( theta ) is varied, the
maximum time taken by a ray to exit
the plane ( mathrm{CD} ) is ( t times 10^{-9} mathrm{s} ), where ( mathrm{t} ) is
[Speed of light ( c=3 x )
( left.10^{8} mathrm{m} / mathrm{s}right] )
12
929A compound microscope has an objective lens of ( 1.0 mathrm{cm} ) focal length and
an eye-piece of ( 2.5 mathrm{cm} ) of focal length.
When the object is placed at ( 1.1 mathrm{cm} ) from the objective, the final image is at the least distance of direct vision. Thus,
the magnification produced is
A . 10
B. 11
( c .100 )
D. 110
12
930What is the angle of the prism for which there will be no emergent ray from the prism if ( C ) is the critical angle ( ? )
A . 2
B. less than 2C
c. more than 2 C
D. None of these
12
931A ray of light from denser medium strikes a rarer medium at angle of incidence ( i . ) The reflected and refracted
rays make an angle of ( 90^{circ} ) with each
other. The angle of reflection and
refraction are ( r ) and ( r^{prime} . ) The critical
angle is
A ( cdot sin ^{-1}(tan r) )
B. ( sin ^{-1}(tan i) )
c. ( sin ^{-1}left(tan r^{prime}right) )
D. ( sin ^{-1}(tan (i+r)) )
12
932What happens when white light passes through a glass prism?
A. Light dispersion and formation of a 7 colors spectrum.
B. Light dispersion and formation of a 6 colors spectrum.
c. Light reflection and a formation of a 6 colors spectrum.
D. Light reflection and a formation of a 7 colors spectrum.
12
933In spectrum obtained with prism which color is deviated maximum?
A . Violet
B. Redd
c. Green
D. orange
12
934State whether the following statement
is True or False.

A shaving mirror is a concave mirror
A. True
B. False

12
935The refracting angle of a prism is 2radians. Refractive indices of its
material for violet and red are
respectively 1.62 and ( 1.5 . ) Dispersion produced by it is
A . 0.24
B. 0.06
c. 1.66
D. 1.12
12
936The diagram below shows two
transparent materials-material G and
material P. The black path is the path of
a light ray through the materials.
Which of the following statement is
true?
A. The sine of the angle that the light ray makes with the normal in substance G is greater than the sine of the angle that the light ray makes with the normal in substance P
B. Light travels more slowly in material P than it does in material G
C. Material G must be air of vacuum
D. Material P must be air or a vacuum
E. The index of refraction of substance ( P ) is less than the
index of refraction of substance
12
937A plane mirror is used as a magnifying
glass. This statement is:
A. True
B. False
12
938A ray ol IIght Is Incıdent normally orn orne
face of a prism as shown in figure. The
refractive index of the material of the
5
prism is ( frac{-a n d}{3} ) the prism is immersed
in water of refractive index ( frac{x}{2} ) then 3
This question has multiple correct options
A ( cdot ) The angle of emergence ( Theta_{2} ) of the ray is ( sin ^{-1}left(frac{5}{8}right) )
B. The angle of emergence ( Theta_{2} ) of the ray is ( sin ^{-1}left(frac{5}{4 sqrt{3}}right) )
C the angle of emergence ( Theta_{2} ) of the ray is ( sin ^{-1}left(frac{7}{3 sqrt{4}}right) )
D. Total internal reflection will not occur at P if the refractive index of water increases to a value greater
( operatorname{than} frac{5}{2 sqrt{3}} ) by dissolving some substance
12
939Fill in the blanks to complete the
following sentences:
i) A ray travelling towards the mirror is
the
ii) Angle between reflected ray and normal is the
iii) The angle between reflecting
surface and the reflected ray is the
A. i-incident ray, ii-angle of reflection, iii-glancing angle of reflection
B. i-normal ray, ii-glancing angle of reflection, liii-angle of incidence
C. i-reflected ray, ,ii glancing angle of incidence , iiiglancing angle of reflection
D. i-reflected ray, ,ii-angle of incidence, iii- angle of reflection
12
940Alternate inverted prisms are placed in series. Choose correct options.
A. Even number of prisms does not produce a spectrum
B. Odd number of prisms produce a spectrum
c. More the number of prisms, less is the intensity of emergent ray/spectrum
D. All of above
12
941The distance between a convex lens and
a plane mirror is ( 10 mathrm{cm} . ) The paralle rays incident on the convex lens, after
reflection from the mirror, form image at the optical centre of the lens. Draw ray-diagram and find out the focal length of the lens.
12
942For reading small letters with a lens
A. one has to keep a convex lens at a distance between ( F ) and ( 2 mathrm{F} ) from the book.
B. one has to keep a concave lens at a distance less than the focal length from the book
C. one has to keep concave lens at a distance between and ( 2 mathrm{F} ) from the book
D. One has to keep a convex lens at a distance less than the an focal length from the book
E. None of these
12
943The beautiful natural phenomenon of
the rainbow is a combination of which
of the following different phenomena?
A. Refraction, reflection
B. Dispersion, refraction
c. Refraction, dispersion, reflection
D. Reflection, dispersion
12
944A linear object ( A B ) is placed along the axis of a concave mirror. The object is moving towards the mirror with speed
( U . ) The speed of the image of the point ( A )
is ( 4 U ) and the speed of the image of ( B )
is also ( 4 U ) but in opposite direction. If
the center of the line ( A B ) is at a
distance ( L ) from the mirror then find out
the length of the object.
A ( cdot frac{3 L}{2} )
в. ( frac{5 L}{2} )
( c . L )
D. None of these
12
945( A ) film projector magnifies a ( 100 mathrm{cm}^{2} ) film strip on a screen. If the linear
magnification is ( 4, ) the area of the magnified film on the screen is be
( 1000 mathrm{cm}^{2} )
A . True
B. False
12
946There is an equiconvex lens of focal length of ( 20 mathrm{cm} ). If the lens is cut into tow equal parts perpendicular to the optical axis, the focal length of each part will be
A. ( 20 mathrm{cm} )
B. 10 ( mathrm{cm} )
c. ( 40 mathrm{cm} )
D. ( 15 mathrm{cm} )
12
947The phenomenon in which light that strikes a surface is thrown back into
the same medium is called –
A. reflection
B. reflex action
c. refraction
D. regression
12
948In our eyes, too much exposure to ultraviolet rays causes:
A. cataracts
B. muscular degeneration
c. both A and B
D. neither A nor B
12
949A convex lens of focal length ( 20 mathrm{cm} ) is placed coaxially with a convex mirror of radius of curvature ( 20 mathrm{cm} . ) The two are
kept at ( 15 mathrm{cm} ) apart from each other. ( mathrm{A} ) point object lies ( 60 mathrm{cm} ) in front of the convex lens. Draw a ray diagram to show the formation of the image by the combination. Determine the nature and
position of the image formed.
12
950If the light from a flashlight makes an
angle of ( 30^{circ} ) with the mirror’s
perpendicular, the angle of the reflected
beam will be ( 120^{circ} )
A. True
B. False
12
951When light is refracted, which of the following does not change?
A. Wavelength
B. Frequency
c. velocity
D. Amplitude
12
952In astronomical telescope, the final image is formed at:
A. the least distance of distinct vision
B. the focus of objective lens
c. the focus of the eye lens
D. beyond the focal length of eyepiece
12
953Assertion
Bluish colour predominates in a clear
sky, since blue has a shorter wavelength and is scattered strongly.
Reason
Blue has the shortest wavelength among all colours.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
954A ray of light is incident on the hypotenuse of a right-angled prism after travelling parallel to the base
inside the prism. If ( mu ) is the refractive
index of the material of the prism, the maximum value of the base angle for which light is totally reflected from the hypotenuse is:
A ( cdot sin ^{-1}left(frac{1}{mu}right) )
B. ( tan ^{-1}left(frac{1}{mu}right) )
c. ( sin ^{-1}left(frac{mu-1}{mu}right) )
D ( cdot cos ^{-1}left(frac{1}{mu}right) )
12
955There is a small black dot at the centre
( C ) of a solid glass sphere of refractive index ( mu . ) When seen from outside, comment on the location of the dot.
A. away from ( C ) for all values of ( mu )
B. at ( C ) for all values of ( mu )
( mathbf{c} . ) at ( C ) for ( mu=1.5, ) but away from ( C ) for ( mu neq 1.5 )
D. at ( C ) only for ( sqrt{2} leq mu leq 1.5 )
12
956The split of white light into its constituent colours by a triangular prism is called
A. Dispersion
B. Reflection
c. Refraction
D. Scattering
12
957How would you explain the coincidence of the experimental facts with the results obtained by a ray diagram in terms of behavior of images formed by lenses?12
958In the white light of sun, maximum
scattering by the air molecules present in the earth’s atmosphere is for:
A. red colour
B. yellow colour
c. green colour
D. blue colour
12
959An incident ray strike at a plane mirror
at an angle of ( 15^{0} ) with the mirror. The angle between the reflected ray and incident ray is:
12
960A linear object of height ( 10 mathrm{cm} ) is kept in front of a concave mirror of radius of
curvature ( 15 mathrm{cm}, ) at a distance of ( 10 mathrm{cm} )
The image formed is
A. Magnified and erect
B. Magnified and inverted
c. Diminished and erect
D. Diminished and inverted
12
961Which of the following is not a function of visual aid?
A. It can magnify words
B. Can provide suitable intensity of light
c. can provide suitable material at proper distance
D. All
12
962The formula for the velocity of electromagnetic waves in vacuum is given by
A. ( c=sqrt{mu_{0} varepsilon} )
B. ( c=frac{1}{sqrt{mu_{0} varepsilon_{0}}} )
c. ( _{c}=sqrt{frac{mu_{0}}{varepsilon_{0}}} )
D. ( c=sqrt{frac{varepsilon_{0}}{mu_{0}}} )
12
963Braille system has dot
patterns.
A . 62
B. 63
c. 72
D. 73
12
964Diamond is :
A. transparent
B. translucent
c. opaque
D. semi-absorbent
12
9654. A step index fibre has a relative refractive index of 0.88%.
What is the critical angle at the corecladding interface?
(a) 60°
(c) 45°
(d) None of these
(b) 75°
12
966Fill in the blanks:
Very fine particles mainly scatter light.
12
967A hemispherical glass body of radius 10 ( c m ) and refractive index 1.5 is silvered
on its curved surface. A small air bubble
is ( 6 mathrm{cm} ) below the flat surface inside it
along the axis. The position of the
image of the air bubble made by the mirror is seen:
A. ( 14 mathrm{cm} ) below flat surface
B. 20 ( c m ) below flat surface
c. ( 16 mathrm{cm} ) below flat surface
D. ( 30 mathrm{cm} ) below flat surface
12
968Middle vascular coat that darkens the
eye chamber and prevents refraction by absorbing the light rays is:
A. Choroid
B. Sclera
c. Retina
D. cornea
12
969Distances measured below the
principal axis are taken as
A. Positive
B. Negative
c. None
D. Both
12
970Assertion: Different colours travel with
different speed in vacuum.

Reason: Wavelength of light depends on refractive index of medium.
A. Both assertion and reason are true but the reason is the correct explanation of assertion
B. Both assertion and reason are true but the reason is not the correct explanation of assertion
c. Assertion is true but reason is false
D. Both the assertion and reason are false
E. Reason is true but assertion is false

12
971What are the two most common defects
of vision (or defect of eye)? How are they
corrected?
12
972A person has a ( 15 mathrm{cm} ) wide face and his
two eyes are separated by ( 9 mathrm{cm} . ) The minimum width of a mirror required for
the person to view his complete face literally is
( mathbf{A} cdot 15 mathrm{cm} )
в. 9 ст
( c .6 c m )
D. 3 cm
12
973Find the odd one form the brackets and
give reason behind your selection. [Blur, Yellow ,Red,Green]
12
974Copy and complete the following ray
( operatorname{diagram} .left(i_{c}=42^{circ}right) )
12
975The image on the retina remains for :
A . ( 20 s )
B. ( 10 s )
c. ( frac{1}{10} s )
D. ( frac{1}{16} )
12
976A converging lens of focal length ( f ) is
used as simple microscope. If the least distance of distinct version of the
observer is ( D ) and the lens is held close
to the eye, the magnifying power of the lens is
A. ( D / 2 f )
B. ( f / D )
c. ( frac{D}{f}-1 )
D. ( D / f )
12
977Our eyes function similar to a:
A. Convex lens
B. Concave lens
c. cylindrical lens
D. None of these
12
978Fill in the blank:
A boy blinks his right eye. Mirror image of the boy blinks its ( _{-}-_{-}-_{-}- ) eye
A. both
B. right
c. none
D. left
12
979Object Convex Convex Image Pin ( quad ) Lens ( quad ) Mirror ( quad mathrm{P} )
22.2 ( 32.2 mathrm{cm} )
( 45.8 mathrm{cm} )
To find the focal length of a convex mirror, a student records the following
data:

The focal length of the convex lens is ( boldsymbol{f}_{1} )
and that of mirror is ( f_{2} ). Then taking
index correction to be negligibly small,
( boldsymbol{f}_{1} ) and ( boldsymbol{f}_{2} ) are close to :
( mathbf{A} cdot f_{1}=7.8 mathrm{cm} quad f_{2}=12.7 mathrm{cm} )
B ( cdot f_{1}=12.7 mathrm{cm} quad f_{2}=7.8 mathrm{cm} )
( mathbf{c} cdot f_{1}=7.8 mathrm{cm} quad f_{2}=25.4 mathrm{cm} )
D. ( f_{1}=15.6 mathrm{cm} quad f_{2}=25.4 mathrm{cm} )

12
980When an object is placed between optical centre and focus of lens:
A. Inverted, real and enlarged image is formed
B. Virtual, erect and enlarged image is formed
c. Inverted, erect, diminished image is formed
D. Virtual, real, diminished image is formed
12
981What is refraction?
A. Phenomenon in which ray of light deviates from its path at the surface of separation of two media.
B. Phenomenon in which ray of light reflects from its path at the surface of separation of two media.
C. Phenomenon in which ray of light deviates from its path at the surface of 1st media
D. None
12
982A ……. eye cannot distinctly see the
objects that are too near.
A. Myopic
B. Presbyopic
c. Hypermetropic
D. Heterophoria
12
983Find out the letters of English alphabet or any other language known to you in which the image formed in a plane
mirror appears exactly like the letter itself. Discuss your findings.
12
984A plane mirror forms image ( I ) of an object 0 kept ( 10 mathrm{cm} ) from the mirror. It is
found that when a Plano concave thin
lens is placed in front of and in contact with the mirror (plane surface of lens in contact with mirror), the position of
image formed by plane mirror does not change. Then the refractive index of lens and radius of curvature of its curved
surface are respectively:
A. ( 1.5,10 mathrm{cm} )
B. ( 2.5,10 mathrm{cm} )
c. ( sqrt{2}, 10 mathrm{cm} )
D. All of these are possible
12
985Which of the states Snell’s law?
A. Incident ray, refracted ray and the normal at the point of incidence all lies in the same plane
B. ( frac{sin i}{sin r}= ) constant (for a given media)
C. Angle of incidence ( = ) Angle of refraction
D. All
12
986A ray of white light shows no dispersion on emerging from a glass plate (slab). Is there no dispersion inside the glass plate as well?12
987Brilliance of diamond is due to:
A. shape
B. cutting
c. reflection
D. total internal reflection
12
988Due to refraction, when seen from
outside, a coin placed under water in a
bowl, appears to
A. go down
B. come up
c. stay where it is
D. move toward left
12
98956. An object 15 cm high is placed 10 cm from the optical
center of a thin lens. Its image is formed 25 cm from the
optical center on the same side of the lens as the object.
The height of the image is
(a) 2.5 cm
(b) 0.2 cm