Question

A ray of light is incident at ${60}^{\circ }$ on glass-air interface. Find out the total deviation of the ray?

\({​\mu}_{g}\) = $\sqrt{2}$, \({​\mu}_{a}\) = 1

• A. 90°
• B. 30°
• C. 60°
• D. 180°

Answer 1

The correct option is C

60°

Since critical angle is ${45}^0$. All angles above ${45}^0$ will undergo Total Internal Reflection.

$\Pi$ - 2i = Deviation = ${180}^{\circ }$ - 2 \times ${60}^{\circ }$ = ${60}^{\circ }$