Question

Why the sun appears white at noon and reddish at early morning or evening

Answer 1

During sunrise and sunset, light has to travel the farthest than during the other parts of the day to reach the human eye. As the distance of travel through the atmosphere increases during dawn and dusk, light is refracted much more than during noon. Thus the colours of the light having shorter wavelengths fade out leaving only the red wavelength that reach our eyes.

You can see that the scattering of light is more when the Sun is near the horizon

At noon sun is directly overhead so the light rays coming from sun absorb all the visible colours thats why we see sun white coloured. But in evening sun is far away as compared to noon. Light rays scattered due to dust particles present in atmosphere, dust particles absorb all the colours except red. So more is the dust in atmosphere more is scattering of red colour thats why we see sun and its surrounded place reddish.

Answer 2

this is due to phenomenon called scattering of light. at noon sun is directly over head so the light rays coming from sun absorb all the visible colours that's why we see the sun white coloured . but in evening sun is far away as compared to noon . light rays scattered due to dust particles present in atmosphere, dust particles absorb all the colours except red. so more is the dust in atmosphere more scattering of red colour that's why we see sun and it's surrounded place reddish