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 $90^{\circ }$