Q17 of 48 Page 1

State the difference in colours of the Sun observed during sunrise/sunset and noon.

Give explanation for each.

The Sun is red at Sun rise and Sunset. At sunrise and Sunset, the sun is near to the horizon and since the sunlight travels long distance through atmosphere to reach us. This results in the scattering of the most of the blue color present from our line of sight and therefore, we observe sun is red at sunrise and sunset.

But at noon, when the sun it at overhead, the light has to travel shorter distance through atmosphere to reach our eyes and therefore, there is a little scattering of blue color and also the light coming from the overhead has almost all its components in equal proportion and therefore at noon it appears white.


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