Question

a man walks towards a plane mirror with a speed of 3 metre per second with what speed does he approaches image

Answer 1

3m/s itself because in the case of a plane mirror the distance of the object to the mirror and the distance of the image to the mirror is always the same...Hence he will approach at the speed of 3m/s as there is no change in the distance

Answer 2

Same speed because the the magnification is +1 so if object size increases the image size also increases.