Question

What is Brewster's law ? Prove that at angle of polarisation reflected rays and refracted rays are mutually perpendicular

Answer 1

An angle of incidence at which polarized light is perfectly transmitted without reflection through a transparent dielectric surface.

When a beam of light gets passed through a medium is gets scattered. the size of the particles in the medium is of order of wavelength of light. 
When the scattered light is seen perpendicular to the beam of light it appears as plane polarized. 

Answer 2

HEY MATE HERE IS YOUR ANSWER:-

It states that the tangent of polarising angle is equal to the refractive index of the material .

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