Question

A ray of light is traveling in medium 1 with the speed of $3\times {10}^{8}m/s,$ incident at the boundary at an angle of ${60}^0$ and starts traveling with the speed of $2\times {10}^{8}m/s.$ What will be the angle of refraction in medium 2?

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

Answer 1

The correct option is A $\sin r=\frac{1}{\sqrt{3}}$

$\frac{\sin i}{\sin r}=\mu ....\left(i\right)$

$\mu =\frac{v_1}{v_2}.....\left(ii\right)$

So, $\frac{\sin {80}^0}{\sin r}=\frac{3\times {10}^8}{2\times {10}^8}$

$\sin r=\frac{\sqrt{3}}{2}\times \frac{2}{3}$

$\sin r=\frac{1}{\sqrt{3}}$