Equal to 53 degrees for an air-water interface, it is given by the inverse tangent of the ratio of the refractive indices.  
This law accounts for why sunglasses work so well at the beach.  Equal to 53 degrees for an air-water interface, it is given by the inverse tangent of the ratio of the refractive indices.  Eponymously named for a Scottish physicist is, for ten points, what angle of incidence at which all light reflected from a surface is polarized?
This law accounts for why sunglasses work so well at the beach.  
Brewster's law or angle (prompt on "polarization" on a first-sentence buzz)