Question

A ray of light is incident on a glass plate at an angle of ${60}^o$. What would be the refractive index of glass, if reflected and refracted rays are perpendicular to each other?

• A. $\sqrt{3}$
• B. $\frac{3}{2}$
• C. $\frac{\sqrt{3}}{2}$
• D. $\frac{1}{2}$

Answer 1

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

$60^\circ $fromnormalis$30^\circ $ from parallel.

[A] $N_1\sin {60}^{\circ }=N_2\sin {30}^{\circ }$

$\begin{array}{c}{N}_1=1\left(air\right)\\ N_2=\frac{\sin 60}{\sin 30}=\frac{\frac{\sqrt{3}}{2}}{\frac{1}{2}}=\sqrt{3}\end{array}$