Question

A ray of light is incident at an angle of incidence ${60}^o$ from air to a liquid, if angle of refraction is ${45}^o$then find refractive index of liquid:

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

Answer 1

The correct option is C $\sqrt{\frac{3}{2}}$

Here angle of incidence $i={60}^0$

And angle of refraction $r={45}^0$

Refractive index$=\frac{angleofincidence}{angleofrefraction}$

$=\frac{\sin 60}{\sin 45}$

$=\frac{\frac{\sqrt{3}}{2}}{\frac{1}{\sqrt{2}}}$

$\sqrt{\frac{3}{2}}$