For a prism of refractive index `1.732`, the angle of minimum deviation is equal to the angle of the prism. The angle of the prism is

Options

A. `80^(@)`
B. `70^(@)`
C. `60^(@)`
D. `50^(@)`

Answer

C

Explanation

`n = (sin ((A + delta_(m))/(2)))/(sin A//2) = (2 sin A// 2 cos A//2)/(sin A//2) [ "as " delta_(m)= A]`
`rArr " " n= 2 cos A//2 `
`rArr (sqrt(3))/(2) = cos A//2 rArr A//2 = 30^(@) rArr A = 60^(@)` .