10 Question-answer on reflection of light
1. A plane mirror is approaching you at 5 cm. per second. You can see your image in it. At what speed will your image approach you?
(a) 10 cm per second
(b) 5 cm per second
(c) 20 cm per second
(d) 15 cm per second
Ans: (a)
2. The number of images observable between two parallel plane mirrors is:
(a) 2
(b) 4
(c) 11
(d) Infinite
Ans: (d)
3. An object is placed symmetrically between the two plane mirrors inclined at an angle of 30, then the total number of images formed is
(a) 12
(b) 2
(c) 11
(d) Infinite
Ans: (c)
4. A man 160 cm. high stands in front of plane mirror. His eyes are at a height of 150 cm. from the floor. Then the minimum length of the plane mirror for him to see his full length image is
(a) 85 cm
(b) 170 cm
(c) 80 cm
(d) 340 cm
Ans: (c)
5. When plane mirror is placed horizontally on level ground at a distance of 60 metres from the foot of a tower, the top of the tower and its image in the mirror subtends at the eye, an angle of 90˚. The height of the tower is:
(a) 30 metre
(b) 60 metre
(c) 90 metre
(d) 120 metre
Ans:( b)
6. A convex mirror is used to form an image of a real object. Then tick the wrong statement.
(a) The image lies between the pole and focus
(b) The image is diminished in size
(c) The image is erect
(d) The image is real
Ans: (d)
7. A virtual image larger than the object can be produced by
(a) Convex mirror
(b) Concave mirror
(c) Refraction and total internal reflection of light
(d) Concave lens
Ans: (b)
8. When light wave suffers reflection, at the interface between air and glass, the change of phase in the reflected wave is equal to
(a) Zero
(b)
2 
radian
(c) Π radian
(d) 3 λ radian
Ans: (c)
9. If an object is 30 cm away from a concave mirror of focal length 15 cm, the image will be
(a) Erect
(b) Virtual
(c) Diminished
(d) Of same size
Ans: (d)
10. It is desired to photograph the image of an object placed at a distance 2 m from the plane mirror. The camera, which is at a distance of 5.5 m from the mirror should be focused for a distance of
(a) 3 m
(b) 4.5 m
(c) 6 m
(d) 7.5 m.
Ans: (d)