Question

A ray of light is incident normally on one of the refracting surfaces of a prism of refracting angle 60${}^0$.

the emergent ray grazes the other refracting surface. The refractive index of the material of the prism is

• A. 1.3
• B. 1.4
• C. 1.155
• D. 1.45

Answer 1

The correct option is C 1.155

$\mu \times sin60=sin90\times 1$
$\mu =\frac{2}{\sqrt{3}}=1.155$