Question

establish Brewster's law of polarisation of light

Answer 1

at polarizing angle reflected Rays and refracted Rays are at 90 degree

Answer 2

Hello mate,

Here is your answer,

Brewster's law, relationship for light waves stating that the maximum polarization (vibration in one plane only) of a ray of light may be achieved by letting the ray fall on a surface of a transparent medium in such a way that the refracted ray makes an angle of 90° with the reflected ray.