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1
PRACTICE SET
OPTICS
CODE- 3006                                        SET-A
Topics Covered: REFLECTION FROM PLANE & SPHERICAL SURFACE AND REFRACTION
THROUGH PLANE SURFACE
INSTRUCTIONS:
(a) Problems from 1-20  are single correct Objective Problems.
(b)   Problems from 21-25 are More than one correct Answer Problems.
(c) Problems from 1-20 carry 4 marks each for correct option and -1 for every wrong attempt.
(d) Problems from 21-25 carry 5 marks each for correct option and 0 for every wrong attempt.

Time: 50 mins.            Max. Marks: 105
1.  An object AB of
length 7.5 cm forms
an inverted image
A’B’ at the same
place, when reflected
from a concave mirror. A parallel ray from top
of the object B, is incident on the mirror at the
point P (not shown in figure). If PB’ = 25cm,
find the focal length of the mirror.
(a) 20 cm   (b) 15 cm
(c) 10 cm   (d) 12.5 cm
2. An object O is placed
between a concave
mirror and a plane
mirror so that the first
image in both the mirrors coincide at I. F is the
focus of concave mirror. What should be the
position of centre of curvature of concave
mirror.
(a) A   (b) B
(c) C   (d) O
3. A square slab is held in air. A ray
of light strikes in the middle of
face PQ at O
1
so that it is
internally reflected to strike again
at O
1
. Find the angle of
incidence, ? :
(a) 30
0
(b) 45
0

(c) 60
0
(d) 90
0

4. A concave mirror of radius of curvature h is
placed at the bottom of a tank containing a
liquid of refractive index ? upto a depth d. An
object P is placed at height h above the bottom
of the mirror. Outside the liquid, an observer O
views the object and its image in the mirror. The
apparent distance between these two will be :
P
h
d
O

(a) zero    (b)
2h
?

(c)
1
h1
??
?
??
?
??
(d)
2h
1 ??

5. An object is placed before a spherical mirror at a
distance u. Its erect image is magnified six
times. Find the distance between focus and the
object :
(a) u/4   (b) u/5
(c) u/7   (d) u/3
6. The distance between object and its erect but
diminished image formed due to a spherical
mirror is 3 times the distance between image
and the focus while distance between object and
focus is 2u. If the image is half in size than the
object, find the distance of the object from the
mirror:
(a)
3u
2
(b)
u
2

(c) u   (d)
3u
4

P
Q
R
S
?
O
1
C B O A I
F
A
A’
B
B’
Page 2

1
PRACTICE SET
OPTICS
CODE- 3006                                        SET-A
Topics Covered: REFLECTION FROM PLANE & SPHERICAL SURFACE AND REFRACTION
THROUGH PLANE SURFACE
INSTRUCTIONS:
(a) Problems from 1-20  are single correct Objective Problems.
(b)   Problems from 21-25 are More than one correct Answer Problems.
(c) Problems from 1-20 carry 4 marks each for correct option and -1 for every wrong attempt.
(d) Problems from 21-25 carry 5 marks each for correct option and 0 for every wrong attempt.

Time: 50 mins.            Max. Marks: 105
1.  An object AB of
length 7.5 cm forms
an inverted image
A’B’ at the same
place, when reflected
from a concave mirror. A parallel ray from top
of the object B, is incident on the mirror at the
point P (not shown in figure). If PB’ = 25cm,
find the focal length of the mirror.
(a) 20 cm   (b) 15 cm
(c) 10 cm   (d) 12.5 cm
2. An object O is placed
between a concave
mirror and a plane
mirror so that the first
image in both the mirrors coincide at I. F is the
focus of concave mirror. What should be the
position of centre of curvature of concave
mirror.
(a) A   (b) B
(c) C   (d) O
3. A square slab is held in air. A ray
of light strikes in the middle of
face PQ at O
1
so that it is
internally reflected to strike again
at O
1
. Find the angle of
incidence, ? :
(a) 30
0
(b) 45
0

(c) 60
0
(d) 90
0

4. A concave mirror of radius of curvature h is
placed at the bottom of a tank containing a
liquid of refractive index ? upto a depth d. An
object P is placed at height h above the bottom
of the mirror. Outside the liquid, an observer O
views the object and its image in the mirror. The
apparent distance between these two will be :
P
h
d
O

(a) zero    (b)
2h
?

(c)
1
h1
??
?
??
?
??
(d)
2h
1 ??

5. An object is placed before a spherical mirror at a
distance u. Its erect image is magnified six
times. Find the distance between focus and the
object :
(a) u/4   (b) u/5
(c) u/7   (d) u/3
6. The distance between object and its erect but
diminished image formed due to a spherical
mirror is 3 times the distance between image
and the focus while distance between object and
focus is 2u. If the image is half in size than the
object, find the distance of the object from the
mirror:
(a)
3u
2
(b)
u
2

(c) u   (d)
3u
4

P
Q
R
S
?
O
1
C B O A I
F
A
A’
B
B’

2
PRACTICE SET
OPTICS
7. P, F and C are the pole, focus and centre of
curvature of a convex mirror. There are two
positions of images
l2
and as shown, for an
virtual object placed at different positions. The
positions of the virtual object corresponding to
I
1
and I
2
respectively will be:
I
1
P F C I
2

(a) between F and C, between C and I
2

(b) between P and F, between F and C
(c) between P and C, between, C and I
2

(d) between P and F, between C and I
2

8. In a vessel, as shown, point P is just visible
when no liquid is filled in vessel through a
telescope in the air. When liquid is filled in the
vessel completely, point Q is visible without
moving the vessel or telescope. Find the
refractive index of the liquid.
2R
R R
A
R R
Q
B
C
D
P
E

(a) 2   (b) 3
(c)
14
3
(d)
85
5

9. In the previous problem, what will be refractive
index of the liquid so that point E is visible
(PE = R/3) through the telescope in air when the
vessel is filled with liquid completely, without
moving the telescope and vessel :
(a) 2   (b) 3
(c) 1.5   (d) none of these
For Problems (10-11)
An object AB of height 1 cm lying on the axis of
convex mirror of focal length 20 cm, at a distance of
30 cm from its pole as shown in figure. Now the
object starts moving with a constant speed 1 cm/sec
towards the pole. Calculate
1cm/s
1cm
O
30cm 20cm
F C

10. Magnitude of velocity of image at the given
instant
(a) 0.16 cm/sec  (b) 0.32 cm/sec
(c) 0.08 cm/sec  (d) 0.64 cm/sec
11. Rate of change of height of image.
(a) 0.016 cm/s  (b) 0.008 cm/s
(c) 0.16 cm/s  (d) 0.004 cm/s
12. A cube of side 2 m is placed in front of a
concave mirror of focal length 1 m with its
face A at a distance of 3 m and face B at a
distance of 5 m form the mirror, The distance
between the images of face A and B and
height of images of A and B are respectively.
2m
B A
3m
2m

(a) 1m, 0.5, 0.25 m  (b) 0.5 m, 1m, 0.25 m
(c) 0.5 m, 0.25 m, 1n (d) 0.25 m, 1m, 0.5 m.
13. A fish rising vertically up toward the surface
of water with speed 3 ms
?1
observes a bird
diving vertically down towards it with speed
9 ms
?1
. The actual velocity of bird is:

(a)4.5 ms
-1
(b) . ms
?1
54
(c) . ms
?1
30  (d) . ms
?1
34
Page 3

1
PRACTICE SET
OPTICS
CODE- 3006                                        SET-A
Topics Covered: REFLECTION FROM PLANE & SPHERICAL SURFACE AND REFRACTION
THROUGH PLANE SURFACE
INSTRUCTIONS:
(a) Problems from 1-20  are single correct Objective Problems.
(b)   Problems from 21-25 are More than one correct Answer Problems.
(c) Problems from 1-20 carry 4 marks each for correct option and -1 for every wrong attempt.
(d) Problems from 21-25 carry 5 marks each for correct option and 0 for every wrong attempt.

Time: 50 mins.            Max. Marks: 105
1.  An object AB of
length 7.5 cm forms
an inverted image
A’B’ at the same
place, when reflected
from a concave mirror. A parallel ray from top
of the object B, is incident on the mirror at the
point P (not shown in figure). If PB’ = 25cm,
find the focal length of the mirror.
(a) 20 cm   (b) 15 cm
(c) 10 cm   (d) 12.5 cm
2. An object O is placed
between a concave
mirror and a plane
mirror so that the first
image in both the mirrors coincide at I. F is the
focus of concave mirror. What should be the
position of centre of curvature of concave
mirror.
(a) A   (b) B
(c) C   (d) O
3. A square slab is held in air. A ray
of light strikes in the middle of
face PQ at O
1
so that it is
internally reflected to strike again
at O
1
. Find the angle of
incidence, ? :
(a) 30
0
(b) 45
0

(c) 60
0
(d) 90
0

4. A concave mirror of radius of curvature h is
placed at the bottom of a tank containing a
liquid of refractive index ? upto a depth d. An
object P is placed at height h above the bottom
of the mirror. Outside the liquid, an observer O
views the object and its image in the mirror. The
apparent distance between these two will be :
P
h
d
O

(a) zero    (b)
2h
?

(c)
1
h1
??
?
??
?
??
(d)
2h
1 ??

5. An object is placed before a spherical mirror at a
distance u. Its erect image is magnified six
times. Find the distance between focus and the
object :
(a) u/4   (b) u/5
(c) u/7   (d) u/3
6. The distance between object and its erect but
diminished image formed due to a spherical
mirror is 3 times the distance between image
and the focus while distance between object and
focus is 2u. If the image is half in size than the
object, find the distance of the object from the
mirror:
(a)
3u
2
(b)
u
2

(c) u   (d)
3u
4

P
Q
R
S
?
O
1
C B O A I
F
A
A’
B
B’

2
PRACTICE SET
OPTICS
7. P, F and C are the pole, focus and centre of
curvature of a convex mirror. There are two
positions of images
l2
and as shown, for an
virtual object placed at different positions. The
positions of the virtual object corresponding to
I
1
and I
2
respectively will be:
I
1
P F C I
2

(a) between F and C, between C and I
2

(b) between P and F, between F and C
(c) between P and C, between, C and I
2

(d) between P and F, between C and I
2

8. In a vessel, as shown, point P is just visible
when no liquid is filled in vessel through a
telescope in the air. When liquid is filled in the
vessel completely, point Q is visible without
moving the vessel or telescope. Find the
refractive index of the liquid.
2R
R R
A
R R
Q
B
C
D
P
E

(a) 2   (b) 3
(c)
14
3
(d)
85
5

9. In the previous problem, what will be refractive
index of the liquid so that point E is visible
(PE = R/3) through the telescope in air when the
vessel is filled with liquid completely, without
moving the telescope and vessel :
(a) 2   (b) 3
(c) 1.5   (d) none of these
For Problems (10-11)
An object AB of height 1 cm lying on the axis of
convex mirror of focal length 20 cm, at a distance of
30 cm from its pole as shown in figure. Now the
object starts moving with a constant speed 1 cm/sec
towards the pole. Calculate
1cm/s
1cm
O
30cm 20cm
F C

10. Magnitude of velocity of image at the given
instant
(a) 0.16 cm/sec  (b) 0.32 cm/sec
(c) 0.08 cm/sec  (d) 0.64 cm/sec
11. Rate of change of height of image.
(a) 0.016 cm/s  (b) 0.008 cm/s
(c) 0.16 cm/s  (d) 0.004 cm/s
12. A cube of side 2 m is placed in front of a
concave mirror of focal length 1 m with its
face A at a distance of 3 m and face B at a
distance of 5 m form the mirror, The distance
between the images of face A and B and
height of images of A and B are respectively.
2m
B A
3m
2m

(a) 1m, 0.5, 0.25 m  (b) 0.5 m, 1m, 0.25 m
(c) 0.5 m, 0.25 m, 1n (d) 0.25 m, 1m, 0.5 m.
13. A fish rising vertically up toward the surface
of water with speed 3 ms
?1
observes a bird
diving vertically down towards it with speed
9 ms
?1
. The actual velocity of bird is:

(a)4.5 ms
-1
(b) . ms
?1
54
(c) . ms
?1
30  (d) . ms
?1
34

3
CLASS QUIZ -  LAWS OF MOTION

TEST- CODE-3107-BOOKLET CODE-B
PRACTICE SET
OPTICS
14. A concave mirror of focal length 10 cm and a
convex mirror of focal length 15 cm are
placed facing each other 40 cm apart. A point
object is placed between the mirrors, on their
common axis and 15 cm from the concave
mirror. Find the position and nature of the
image produced by the successive reflections,
first at concave mirror and then at convex
mirror.
(a) 12 cm behind convex mirror, real
(b) 9 cm behind convex mirror, real
(c) 6 cm behind convex mirror, virtual
(d)  3 cm behind convex mirror, virtual
15. A linear object AB 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 4U and the
speed of the image of B is also 4U but in
opposite direction. If the center of the line
AB is at a distance L from the mirror then
find out the length of the object.

A B

(a) 3L/2  (b) 5L/3
(c) L   (d) None
16. In a thick glass slab of thickness and
refractive index n
1,
a cuboidal cavity of
thickness ‘m’ is carved as shown in the fig
and is filled with liquid of R.I. n
2
(n
1
> n
2
).
The ratio of /m , so that shift produced by
this slab is zero when an observer A observes
an object B with paraxial rays is:
1
2 m
l
B
A
air
n
2
air

(a)
?
?
12
2
nn
n1
(b)
?
?
12
21
nn
n (n 1)

(c)
?
?
12
1
nn
n1
(d)
?
?
12
12
nn
n (n 1)

17. In the fig shown find the total magnification
after two successive reflections first on M
1
&
then on M
2

(a) +1   (b) ?2
(c) +2   (d) ?1
18. A particle revolves in clockwise direction (as
seen from point A) in a circle C of radius
1cm and completes on revolution in 2 sec.
The axis of the circle and the principal axis of
the mirror M coincide, call it AB. The radius
of curvature of the mirror is 20cm. Then the
direction of revolution (as seen from A) of
the image of the particle and its speed is

(a) clockwise, 1.57 cms
-1

(b) clockwise, 3.14 cms
-1
(c) anticlockwise, 1.57 cms
-1
(d) anticlockwise, 3.14 cms
-1

19. Choose the correct mirror – image of figure
given below

Page 4

1
PRACTICE SET
OPTICS
CODE- 3006                                        SET-A
Topics Covered: REFLECTION FROM PLANE & SPHERICAL SURFACE AND REFRACTION
THROUGH PLANE SURFACE
INSTRUCTIONS:
(a) Problems from 1-20  are single correct Objective Problems.
(b)   Problems from 21-25 are More than one correct Answer Problems.
(c) Problems from 1-20 carry 4 marks each for correct option and -1 for every wrong attempt.
(d) Problems from 21-25 carry 5 marks each for correct option and 0 for every wrong attempt.

Time: 50 mins.            Max. Marks: 105
1.  An object AB of
length 7.5 cm forms
an inverted image
A’B’ at the same
place, when reflected
from a concave mirror. A parallel ray from top
of the object B, is incident on the mirror at the
point P (not shown in figure). If PB’ = 25cm,
find the focal length of the mirror.
(a) 20 cm   (b) 15 cm
(c) 10 cm   (d) 12.5 cm
2. An object O is placed
between a concave
mirror and a plane
mirror so that the first
image in both the mirrors coincide at I. F is the
focus of concave mirror. What should be the
position of centre of curvature of concave
mirror.
(a) A   (b) B
(c) C   (d) O
3. A square slab is held in air. A ray
of light strikes in the middle of
face PQ at O
1
so that it is
internally reflected to strike again
at O
1
. Find the angle of
incidence, ? :
(a) 30
0
(b) 45
0

(c) 60
0
(d) 90
0

4. A concave mirror of radius of curvature h is
placed at the bottom of a tank containing a
liquid of refractive index ? upto a depth d. An
object P is placed at height h above the bottom
of the mirror. Outside the liquid, an observer O
views the object and its image in the mirror. The
apparent distance between these two will be :
P
h
d
O

(a) zero    (b)
2h
?

(c)
1
h1
??
?
??
?
??
(d)
2h
1 ??

5. An object is placed before a spherical mirror at a
distance u. Its erect image is magnified six
times. Find the distance between focus and the
object :
(a) u/4   (b) u/5
(c) u/7   (d) u/3
6. The distance between object and its erect but
diminished image formed due to a spherical
mirror is 3 times the distance between image
and the focus while distance between object and
focus is 2u. If the image is half in size than the
object, find the distance of the object from the
mirror:
(a)
3u
2
(b)
u
2

(c) u   (d)
3u
4

P
Q
R
S
?
O
1
C B O A I
F
A
A’
B
B’

2
PRACTICE SET
OPTICS
7. P, F and C are the pole, focus and centre of
curvature of a convex mirror. There are two
positions of images
l2
and as shown, for an
virtual object placed at different positions. The
positions of the virtual object corresponding to
I
1
and I
2
respectively will be:
I
1
P F C I
2

(a) between F and C, between C and I
2

(b) between P and F, between F and C
(c) between P and C, between, C and I
2

(d) between P and F, between C and I
2

8. In a vessel, as shown, point P is just visible
when no liquid is filled in vessel through a
telescope in the air. When liquid is filled in the
vessel completely, point Q is visible without
moving the vessel or telescope. Find the
refractive index of the liquid.
2R
R R
A
R R
Q
B
C
D
P
E

(a) 2   (b) 3
(c)
14
3
(d)
85
5

9. In the previous problem, what will be refractive
index of the liquid so that point E is visible
(PE = R/3) through the telescope in air when the
vessel is filled with liquid completely, without
moving the telescope and vessel :
(a) 2   (b) 3
(c) 1.5   (d) none of these
For Problems (10-11)
An object AB of height 1 cm lying on the axis of
convex mirror of focal length 20 cm, at a distance of
30 cm from its pole as shown in figure. Now the
object starts moving with a constant speed 1 cm/sec
towards the pole. Calculate
1cm/s
1cm
O
30cm 20cm
F C

10. Magnitude of velocity of image at the given
instant
(a) 0.16 cm/sec  (b) 0.32 cm/sec
(c) 0.08 cm/sec  (d) 0.64 cm/sec
11. Rate of change of height of image.
(a) 0.016 cm/s  (b) 0.008 cm/s
(c) 0.16 cm/s  (d) 0.004 cm/s
12. A cube of side 2 m is placed in front of a
concave mirror of focal length 1 m with its
face A at a distance of 3 m and face B at a
distance of 5 m form the mirror, The distance
between the images of face A and B and
height of images of A and B are respectively.
2m
B A
3m
2m

(a) 1m, 0.5, 0.25 m  (b) 0.5 m, 1m, 0.25 m
(c) 0.5 m, 0.25 m, 1n (d) 0.25 m, 1m, 0.5 m.
13. A fish rising vertically up toward the surface
of water with speed 3 ms
?1
observes a bird
diving vertically down towards it with speed
9 ms
?1
. The actual velocity of bird is:

(a)4.5 ms
-1
(b) . ms
?1
54
(c) . ms
?1
30  (d) . ms
?1
34

3
CLASS QUIZ -  LAWS OF MOTION

TEST- CODE-3107-BOOKLET CODE-B
PRACTICE SET
OPTICS
14. A concave mirror of focal length 10 cm and a
convex mirror of focal length 15 cm are
placed facing each other 40 cm apart. A point
object is placed between the mirrors, on their
common axis and 15 cm from the concave
mirror. Find the position and nature of the
image produced by the successive reflections,
first at concave mirror and then at convex
mirror.
(a) 12 cm behind convex mirror, real
(b) 9 cm behind convex mirror, real
(c) 6 cm behind convex mirror, virtual
(d)  3 cm behind convex mirror, virtual
15. A linear object AB 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 4U and the
speed of the image of B is also 4U but in
opposite direction. If the center of the line
AB is at a distance L from the mirror then
find out the length of the object.

A B

(a) 3L/2  (b) 5L/3
(c) L   (d) None
16. In a thick glass slab of thickness and
refractive index n
1,
a cuboidal cavity of
thickness ‘m’ is carved as shown in the fig
and is filled with liquid of R.I. n
2
(n
1
> n
2
).
The ratio of /m , so that shift produced by
this slab is zero when an observer A observes
an object B with paraxial rays is:
1
2 m
l
B
A
air
n
2
air

(a)
?
?
12
2
nn
n1
(b)
?
?
12
21
nn
n (n 1)

(c)
?
?
12
1
nn
n1
(d)
?
?
12
12
nn
n (n 1)

17. In the fig shown find the total magnification
after two successive reflections first on M
1
&
then on M
2

(a) +1   (b) ?2
(c) +2   (d) ?1
18. A particle revolves in clockwise direction (as
seen from point A) in a circle C of radius
1cm and completes on revolution in 2 sec.
The axis of the circle and the principal axis of
the mirror M coincide, call it AB. The radius
of curvature of the mirror is 20cm. Then the
direction of revolution (as seen from A) of
the image of the particle and its speed is

(a) clockwise, 1.57 cms
-1

(b) clockwise, 3.14 cms
-1
(c) anticlockwise, 1.57 cms
-1
(d) anticlockwise, 3.14 cms
-1

19. Choose the correct mirror – image of figure
given below

4
PRACTICE SET
OPTICS
20. A point object is placed in front of a thick
plane mirror as shown in figure below. Find
the location of final image w.r.t. object.
?=3/2
10cm
5cm
O

(a)
15
cm
2
(b) 15 cm
(c)
40
cm
3
(d)
80
cm
3

21. The diagram below shows
an object located at point P,
0.25 metre from concave
spherical mirror with
principal focus F. The focal length of the
mirror is 0.10 metre.
How does the image change s the object is
moved from point P toward point F?
(a) Its distance from the mirror decreases
(b) The size of image decrease
(c) Its distance from the mirror increases
(d) The size of image increases
22. An object AB is placed parallel and close to
the optical axis between focus F and centre of
curvature C of a converging mirror of focal
length f as shown in figure.
A B
F C

(a)  Image of A will be close than that of B
from the mirror.
(b)  Image of AB will be parallel to the
optical axis.
(c)  Image of AB will be straight line
inclined to the optical axis.
(d)  Image of AB will not be straight line.
23. Which of the following statements is/are
correct about the refraction of light from a
plane surface when light ray is incident in
denser medium. [C is critical angle]
(a)  The maximum angle of deviation during
refraction is C
2
?
??
?
??
??
, it will be at angle
of  incidence is C.
(b)  The maximum angle of deviation for all
angle of incidences is 2C ?? , when angle
of  incidence is slightly greater than C.
(c)  If angle of incidence is less than C then
deviation increases if angle of incidence
is also increased.
(d)  If angle of incidence is greater than C
then angle of deviation decreases if angle
of incidence is increased.
24. A fish F, in the pond is at a depth of 0.8 m
from the water surface and is moving
vertically upwards with velocity 2 ms
-1
. At
the same instant a bird B is at a height of 6 m
from the water surface and is moving
downwards with velocity 3 ms
-1
. At this
instant both are on the same vertical lines as
shown in the figure. Which of the following
statements are correct?
B
6m
3 ms
?1
2 ms
?1
F
0.8m
Air
Water
( =4/3) ?

(a)  Height of B, observed by F (from itself)
is equal to 5.30 m
(b)  Depth of F, observed by B (from itself)
is equal to 6.60 m
(c)  Height of B, observed by F (from itself)
is equal to 8.80 m
(d)  None of the above
25. In previous question,
(a)  velocity of B, observed by F (relative to
itself) is equal to 4.25 ms
-1

(b)  velocity of B, observed by F (relative to
itself) is equal to 6 ms
-1
(c)  velocity of B, observed by F (relative to
itself) is equal to 5.50 ms
-1
(d)  velocity of F, observed by B (relative to
itself) is equal to 4.50 ms
-1

P F
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