Question

What is the relation between the polarizing angle and refractive index?

Answer 1

1. A polarized light wave refers to a wave whose vibrations are oriented in a specific direction. If unpolarized light is incident on an interface between two media at a certain angle and the reflected light is perfectly polarized, then the angle is said to be the polarizing angle or Brewster's angle.
2. The refractive index of a material indicates how much the incident light will bend when passing through it. It is a dimensionless quantity.
3. According to Brewster's law, the polarizing angle can be related to the refractive index by the relation, ${\theta }_B={\tan }^{-1}\left(\frac{n_2}{n_1}\right)$. Here, ${\theta }_B$ is Brewster's angle, $n_1$ is the refractive index of the medium where the light is incident and $n_2$ is the refractive index of the medium through which the light ray is transmitted.

Hence, the relation between the polarizing angle and refractive index is ${\theta }_B={\tan }^{-1}\left(\frac{n_2}{n_1}\right)$.