One face of a prism with a refrective angle of `30^@` is coated with silver. A ray of light incident on another face at an angle of `45^@` is refracted and reflected from the silver coated face and retraces its path. What is the refractive index of the prism?

Options

A. `1.5`
B. `(3)/(sqrt(2))`
C. `sqrt(2)`
D. `(4)/(3)`

Answer

C

Explanation

`A=r=0impliesr=30^(@)`
`:. mu=(sin i)/(sin r)=(sin 45^(@))/(sin 30^(@))=sqrt(2)`