Chapter 18, Problem 41A

To determine

To explain: The information about the speeds of different colors of light travelling through air.

Explanation of Solution

Introduction:

Refraction occurs when light rays passes from one medium to another of different optical density. Density of air molecules in the Earth’s atmosphere varies with the altitude and hence the light from the Sun gets refracted as it passes through the Earth’s atmosphere.

The sun light is not separated in to its spectrum while passing through the earth’s atmosphere indicates that in air medium the light rays of all the colors travelling with the same speed. Because spectrum of light is produced by a medium, if different colors travel with different speeds through that medium.