When unpolarized light is incident on a transparent refracting medium, at a particular angle of incidence the reflected light and refracted light are perpendicular to each other that angle of incident is known as a polarizing angle.
Since,
Polarization of reflection, the reflected light gets completely plane-polarized and which makes an angle \(\frac{pi }{2}\) with the refracting light.
According to brewster’s law,
ip + r = 90°
r – is angle of refraction
ip – is polarising angle
r = 90° – ip
by snell’s law
μ1 sin i = μ2 sin r
μ1 = 1 and μ2 = μ
\(\frac{sin i}{sin }=\mu\)Where
i = ip and
r = 90° – ip
\(\frac{sin {{i}_{p}}}{sin (90{}^circ -{{i}_{p}})}=\mu\) \(\frac{sin {{i}_{p}}}{cos {{i}_{p}}}=\mu\) \(\tan {{i}_{p}}=\mu\) This relation is known as Brewster angle.
