Q.
Light is incident from a medium $X$ at an angle of incidence $i$ and is refracted into a medium $Y$ at angle of refraction$\ r$. The graph sin $i$ $versus$ sin $r$ is shown in figure. Which of the following conclusions would fit the situation?
1. Speed of light in medium $Y$ is $\sqrt{3}\ $times that in medium $X$
2. Speed of light in medium $Y$ is 1/$\sqrt{3}$ times that in medium $X$
3. Total internal reflection will occur above a certain $i$ value
A) 2 and 3
B) 1 and 3
C) 2 only
D) 3 only
Explanation
(c) $\frac{\sin r}{\sin i} = \tan{30{^\circ} =}\frac{1}{\sqrt{3}}$
Or $\ \frac{\sin i}{\sin r} = \sqrt{3}\ or\ \mu = \sqrt{3}$
So, speed of light in $Y\ is\ \sqrt{3}$ times less
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.