[UPSC CSE 2006] Polarisation and Modern Optics (Q424, 20M)

How would you produce plane polarized light by reflection ? What is Brewster's law ? Calculate the angular position of the sun above the horizon so that light reflected from a calm lake is completely polarized. The refractive index of water is 1.33. Circularly polarized and unpolarized light are passed in turn through a Nicol prism. The Nicol is rotated about the direction of light as axis. What would you observe in each case ? How would you distinguish between them ?