The angle of incidence for an equilateral prism of refractive index `sqrt(3)` so that the ray is parallel to the base inside the prism is

Options

A. `30^(@)`
B. `20^(@)`
C. `60^(@)`
D. `45^(@)`

Answer

C

Explanation

Given, `mu = sqrt3`
Here, `r= (A)/(2) = (60^@)/(2) = 30^(@) " "(because "equilateral prism")`
So, `(sin i)/(sin r) = mu`
`sin i = sqrt(3) sin 30^@`
`sin i = sqrt(3) xx (1)/(2)`
`sin i = (sqrt(3))/(2)`
`i = sin^(-1) ((sqrt3)/(2))`
`i= 60^@`