What process is MOSTLY responsible for the blue appearance of the sky? A) refraction of light by clouds B) scattering of light by air molecules C) refraction of light by water molecules D) obstruction of yellow light by pollutants

1 Answer
Apr 5, 2017

B) scattering of light by air molecules.


The light from the sun looks white. But we know that it is really made up of colors of the rainbow. This can be demonstrated with the help of a prism
As sunlight reaches Earth's atmosphere and is scattered in all directions by the molecules and particles of the atmosphere.

A type of scattering in which selective scattering of light off particles those are no bigger than one-tenth the wavelength of light occurs. This is called Rayleigh scattering. In this type of scattering the intensity of scattered light is inversely proportional to the fourth power of wavelength of light.


Consequently, oxygen and nitrogen molecules in the lower atmosphere scatter blue and violet light, to a greater degree than red and yellow light. Though the atmospheric particles scatter violet more than blue light, the sky appears blue, as our eyes are more sensitive to blue light and also that some of the violet light is absorbed in the upper atmosphere.