A ray of light is incident on a `60^(@)` prism at the minimum deviation position. The angle of refraction at the first face (i.e. incident face) of the prism is-

Options

A. zero
B. `30^(@)`
C. `45^(@)`
D. `60^(@)`

Answer

B

Explanation

Angle of prism, `A=r_(1)+r_(2)` For minimum deviation
`r_(1)=r_(2)=r:.A=2r`
Given, `A=60^(@)`
Hence, `r=(A)/(2)=(60^(@))/(2)=30^(@)`