Now imagine throwing the same balls with equal force, standing in the same places as before, but this time the wall surface isn’t flat. When the balls hit the surface, they will bounce in many different directions.This is the same idea as when a beam of light strikes a rough or irregular surface (such as the bookshelf in your bedroom). Each point on the surface has a different normal line. The angles of reflection will be different at each point on the surface and the light will be reflected in many different directions. This is why a rough surface will be visible from almost any position, while in order to see a reflection in a mirror, your eyes must be in the particular direction that the light is reflected.
