Question

An object is placed 20 cm in front of a plane mirror. The mirror is moved 2 cm towards the object. The distance between the positions of the original and final images seen in the mirror is:

(a) 2 cm
(b) 4 cm
(c) 10 cm
(d) 22 cm

Answer 1

The correct option is (b) 4 cm
Given,

Object distance = 20 cm

The mirror is moved 2 cm towards the object

So,
Distance between original image and final image = distance the mirror moved + same distance the image move= 2 + 2 = 4 cm.