Question

the sky appears blue and the sun appear reddish at sunset and sunrise explain this phenomenon with the reason

Answer 1

sky appears blue because the particles of blue wavelength are of same size as that of particles in sky so it is scattered the most and hence the sky appears blue.

at the time of sunrise and sunset the sun is at maximum distance from Earth so light has to travel maximum distance so light having small wavelength get scattered and the light having maximum wavelength reach our eyes that is red light which have the maximum wavelength.

Answer 2

Light form the Sun near the horizon passes through thicker layers of air and larger distance in the earth's atmosphere before reaching our eyes.The light from the sun overhead would travel relatively shorter distance.At noon, the sun appears white as only a little of the blue and violet colors are scattered.Near the horizon, most of the blue light and shorter wavelengths are scattered away by the particles.This gives rise to the reddish appearance of the sun.

A clear cloudless day-time sky is blue because molecules in the air scatter blue light from the sun more than they scatter red light. When we look towards the sun at sunset, we see red and orange colors because the blue light has been scattered out and away from the line of sight.