For a prism kept in air, it is found that for an angle of incidence `60^(@)` , the angle of refraction 'A', angle of deviation `delta`, and angle of emergence 'e' become equal. The minimum angle of incidence of a ray that will be transmitted through the prism is

Options

A. 1.73
B. 1.15
C. 1.5
D. 1.33

Answer

a.

Explanation

Given `i=60^(@), A=delta=e`
`delta=i+e-ArArr delta=1`
`( :'e=A)` and `delta=i=e`
`mu=(sin((A+delta_(m))/(2)))/("sin"(A)/(2))`
Here, angle of deviation is minimum `( :'i=e)`
`mu=(sin((60^(@)+60^(@))/(2)))/(sin(60^(@)//2))=sqrt(3)`