Question

A beam of light strikes a piece of glass at an angle of incidence of ${60}^{\circ }$ and the reflected beam is completely plane polarized. The refractive index of the glass is equal to

• A. $1.5$
• B. $\sqrt{3}$
• C. $\sqrt{2}$
• D. $3$

Answer 1

The correct option is B $\sqrt{3}$

Given
${\theta }_B={60}^{\circ }$
From Brewster’s law
$\mu =tan\left({\theta }_B\right)$
$\mu =tan\left({60}^{\circ }\right)=\sqrt{3}$