Question

Why does the sky appear blue on a clear day?

Answer 1

The sky appears blue on a clear day because of the scattering of blue light by the air molecules in the earth's atmosphere. The air molecules are much smaller compared with the wavelength of visible light. Therefore, they scatter light of shorter wavelengths more easily and effectively than light of longer wavelengths. Hence, blue light gets scattered very easily because of its shorter wavelength compared with other colours, such as red, orange and yellow.