FTP, name this type of scattering which explains the color of the sky.
This elastic process results from forcing harmonic oscillators below their natural frequency.  It predominates for particles less than one-tenth the wavelength of the incoming radiation, which distinguishes it from the analogous Raman process.  Its namesake calculated that the intensity goes as one over the fourth power of the wavelength, so that the blue end of the optical spectrum is favored.  FTP, name this type of scattering which explains the color of the sky.
This elastic process results from forcing harmonic oscillators below their natural frequency.  
Rayleigh scattering