Scattering and wavelength dependence

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Longer wavelengths are generally less energetic, which may contribute to their scattering behavior, but this is not a universal rule. Shorter wavelengths, such as blue light, are actually scattered more efficiently in the atmosphere, explaining the blue appearance of the sky. The relationship between scattering and wavelength is complex, with atmospheric scattering efficiency inversely proportional to the fourth power of the wavelength for particles much smaller than the wavelength. For larger spheres, the scattering efficiency follows a different relationship based on the size ratio of the sphere to the wavelength. Understanding the nuances of scattering and wavelength dependence requires extensive study.
coke
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i don't know why the longer the wavelenght, the easier for it to be sattered ?
 
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Welcome to PF, Coke.
I have pretty much zero knowledge of optics, but I would suspect that it's simply because longer wavelengths are less energetic. Red light, therefore, would be more likely to be 'diluted' than blue.
There are quite a few guys here who know an awful lot more about the subject, and they'll be with you shortly.
 
It's not always true that longer wavelengths are scattered more. In fact, the sky appears blue because shorter wavelengths are scattered more efficiently in the atmosphere.

In any case, the question can be simply "How does scattering depend on wavelength"? And the answer to that would fill several books. For atmospheric scattering (particles that are much smaller than a wavelength), the scattering efficiency goes as 1/(wavelength)^4. For spheres of arbitrary size, the scattering goes as 1/x^2, where x = radius/wavelength (Mie scattering).
 
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