Answer to Question #189917 in Optics for Pagol

Question

Abid is a mirror-maker. He tries to be very economical when he makes his mirror, meaning he doesn’t want to waste any extra glasses. Now, his job is to make a mirror so that the user can see the whole image of his/her body standing at any distance from the mirror. If the height of the tallest man in the world is 2.5 m, what is the minimum height of the mirror (in meters) Abid needs to ensure?

Answer 1

It does not matter how far you are from the mirror. In order to see full image of a person, the minimum size of the mirror should be one half the person's height. This is so because, in reflection, the angle of incidence is equal to angle of reflection. So, to see the image of a 2.5 m tall person, a 1.25 m long mirror is required.

So Minimum height of mirror must be 1.25m