1.      What is the difference in colours of the Sun observed during sunrise/sunset and noon? Give explanation for each.

Sun appears red at sunrise and sunset : At sinrise and sunset, sun is closer to the horizon. The sunlight passes through denser layer of air and covers larger distance before reaching our eyes. Most of the blue light gets scattered. And red color reaches us which make the sun appears red at sunrise.

At noon, the sun is overhead. The sunlight passes through layers of air and covers shorter distance before reaching our eye. So, almost all colours of light are scattered equally. Hence the sun appears white.