Question

A ray of light, incident on an equilateral prism $({\mu }_g=\sqrt{3})$ moves parallel to the base line of the prism inside it. Find the angle of incidence for this ray.

Answer 1

Since the ray of light moves parallel to the base inside the prism which is at an angle of ${60}^{\circ }$ to the side of triangle where refraction took place, the angle of refraction is ${30}^{\circ }$.

From snell's law,

$sini={\mu }_{g}sinr$

$=\sqrt{3}sin{30}^{\circ }=\frac{\sqrt{3}}{2}$

$⟹i={60}^{\circ }$