Question

A light beam is incident on a piece of fused quartz (n =1.458) at the Brewster angle. find (a) value of Brewster's angle. (b) the angle of refraction for transmitted rays

Answer 1

The Brewster angle (B) is that at which the reflected light is completely polarized. It can be determined from the fact that its tangent is equal to the refractive index of the material it is being reflected by, so tan(B) = n. You can find the angle of refraction from the fact that it is at right angles to angle B or you can find it from Snell's law of refraction,

n1 sin (incidence angle) = n2 sin (refracted angle),

where n1 and n2 are the indices of refraction of, here, air and quartz. 1.00 and 1.458.