Question

A ray $OP$ of monochromatic light is incident on the face $AB$ of prism $ABCD$ near vertex $B$ at an incident angle of $60^{\circ}$ (see figure). If the refractive index of the material of the prism is $\sqrt{3}$, which of the following is (are) correct?

• A. The ray gets totally internally reflected at face CD
• B. The ray comes out through face AD
• C. The angle between the incident ray and the emergent ray is $90^{\circ}$
• D. The angle between the incident ray and the emergent ray is $120^{\circ}$

Answer 1

Answer: (A), (B), (C)

Using snell's law
$\sin ^{-1} \frac{1}{\sqrt{3}}<\sin ^{-1} \frac{1}{\sqrt{2}}$
Net deviation is $90^{\circ}$