Q. When the angle of incidence on a material is $60{^\circ}$, the reflected light is completely polarized. The velocity of the refracted ray inside the material is $\left( in\ ms^{- 1} \right)$
A) $3 \times 10^{8}$
B) $\left\lbrack \frac{3}{\sqrt{2}} \right\rbrack \times 10^{8}$
C) $\sqrt{3} \times 10^{8}$
D) $0.5 \times 10^{8}$
Explanation
(c) From Brewster’s law,
$\mu = \tan i_{p}$
$\Rightarrow \frac{c}{v} = \tan{60{^\circ}} = \ \sqrt{3}$
$\Rightarrow v = \frac{c}{\sqrt{3}} = \frac{3 \times 10^{8}}{\sqrt{3}}$
$= \sqrt{3} \times \frac{10^{8}m}{s}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.