Rain is falling vertically. A man running on the road keeps his umbrella tilted but a man standing on the road keeps his umbrella vertical to protect himself from the rain. But both of them keep their umbrellas vertical to avoid vertical sunrays. Explain.

The question addresses the reader to get the essence of Sir Albert Einstein’s Theory of Relativity. The answer to this question is normally approached with the concept of relative velocity. But we can’t ignore the theory of relativity which appeals to me as the speed of light is constant or independent of the observer. If you are trying to get the velocity of light with respect to man then, it would be useless. This is th ereason why the man running as well as the man who is standing hold umbrella upward.