Question

why sun seen reddish at sun set give reason

Answer 1

As the sun is at a maximum distance from earth during sunset or sunset all other colored lights get scattered due to long distance, as red color has huge wavelength it doesn't get scattered easily. That's why during sunset sun appears red.

Answer 2

the sky is seen reddish during sunset because of the earth rotation the location of the sun comes write in the horizon and because of it light has to travel more distance through earth's atmosphere which consists of air molecules and because of it the red Orange and yellow or the larger wavelength part of light is scattered as per stated in Raleigh scattering the scattering is inversely proportional to the fourth power of the wavelength of light and that answers why the sky is blue because the blue part of wavelength of light is too short
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