Question

1. How can we find Brewster’s angle for light incident on a glass slide?

Answer 1

First of all, what is Brewster's angle ?

A standard definition - An angle of incidence that produces a 90^o angle between the reflected and refracted ray is called the Brewster angle. At Brewster's angle, reflected light waves are all polarized into a single plane.

Now, consider a glass slide placed in an air medium such that light is incident from air to glass.

Here n_glass > n_air

where n is refractive index.

So

tan = n_glass / n_air

= tan^-1 (n_glass / n_air)

n_glass is usually around 1.52 (typical crown glass)

n_air is 1

so,

= 56.6 degrees