Question

An object O is kept 80 cm in front of a plane mirror M. If the mirror is moved 20 cm away from the object. Calculate the image shift from its previous position.

Answer 1

Distance of object from the mirror = 80 cm

Distance between object and its image = 80 + 80 = 160 cm

New distance of object from the mirror= 80 + 20 = 100 cm

Now, distance between object and image = 100 + 100 = 200 cm

Image shift = 200 - 160 = 40 cm