Mon February 21, 2011 By: Prathibha Pillai

sky appears blue due to scattering of shorter wavelength blue color.why the wavelength of blue color is shorter?

Expert Reply
Tue February 22, 2011
Dear student
It is a natural occuring fact that the wavelength of blue colour is short.
The molecules of air and other fine particles in the atmosphere have size
smaller than the wavelength of visible light. These are more effective in
scattering light of shorter wavelengths at the blue end than light of longer
wavelengths at the red end. The red light has a wavelength about 1.8
times greater than blue light. Thus, when sunlight passes through the
atmosphere, the fine particles in air scatter the blue colour (shorter
wavelengths) more strongly than red. The scattered blue light enters
our eyes.
Hope this helps.
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