Question

A man is going away from the plane mirror with a velocity of 5 m/s. With what velocity is he going away from his own image in the mirror?

Answer 1

We know that the image formed by a plane mirror is as much behind the mirror as object is in front. So, the speed of image will be same as object but in opposite direction. Thus, net velocity between man and his image will be 3 - (-3) = 6 m/s.