Question

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

Answer 1

Answer:

4cm

Explanation:

Initially, the object is placed 20 cm in front of mirror. So the image will form 20 cm behind the mirror.

If mirror is moved 2 cm towards the object,

distance between object and mirror = 20 cm - 2 cm = 18 cm

distance between mirror and image = 18 cm, which is 2 cm less than the initial case.

Since, the mirror has also moved 2 cm away from the position of original image, so the total distance between the positions of the original and final images is 2 cm + 2 cm = 4 cm