Question

Arrange the following steps in a sequential order to determine the focal length of a concave mirror by distant object method.
(A) Place a white screen in front of the mirror and adjust the position of the screen until a sharp images is formed.
(B) Focus the mirror towards a distant object.
(C) Mount the concave mirror on a mirror stand.
(D) Measure the distance between the screen and the mirror. This gives the focal length.
A. C A B D
B. C B A D
C. B A C D
D. A B D C

Answer 1

Correct Answer - B
The concave mirror is mounted on the stand (c ). The mirror is focussed towards the object (b) . A white screen is placed in front of the mirror and its position is adjusted to get a clear image (a). The distance between the screen and the mirror gives the focal length (d).