Can anyone explain why sky is blue?
Because the atmosphere is better at scattering blue light than light of other colors.
See Rayleigh scattering in our atmosphere:
The scattered blue light is polarized because of this.
Welcome to PF!
Hello kambez! Welcome to PF!
It's because scattering is inversely prooprotional to the fourth power of wavelength … see http://en.wikipedia.org/wiki/Rayleigh_scattering#Rayleigh_scattering_from_molecules" …
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