Q. A ray is incident at an angle of incidence $i$ on one surface of a prism of small angle $A$ and emerges normally from the opposite surface. If the refractive index of the material of the prism is $\mu$, the angle of incidence $i$ is nearly equal to
A) $A/\mu$
B) $A/2\mu$
C) $\mu A$
D) $\mu A/2$
Explanation
(c) Since the ray emerges normally, therefore $e = 0$
According to relation $A + \delta = i + e,$ we get $i = A + \delta$
Hence by $\delta = (\mu - 1)A,$ we get $i = \mu A$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.