A ray of light is incident normally on one of the faces of a prism of apex angle 30 degree and refractive index `sqrt2`. The angle of deviation of the ray is…degrees.

Options

A. `26^(@)`
B. `0^(@)`
C. `23^(@)`
D. `15^(@)`

Answer

D

Explanation

`A=30^(@), mu=sqrt(2), ` As we known
`A=r_(1)+r_(2)=0+r_(2)impliesA=r_(2)`.
Applying Snell's law for the surface `AC`
`(1)/(mu)=(sin r_(2))/(sine)=(sin A)/(sine)implies(sin 30^(@))/(sin e)impliese=45^(@)`
`delta=e-r_(2)=45^(@)-30^(@)=15^(@)`