When light of wavelength `lambda` on an equilateral prism, kept on its minimum deviation position, it is found that the angle of deviation equals the angle the angle of the prism itself. The refractive index of the material of the prism for the wavelength `lambda` is

Options

A. `sqrt(3)`
B. `(sqrt(3))/(2)`
C. 2
D. `sqrt(2)`

Answer

A

Explanation

`n = (sin( (A+ delta_(m))/(2) ) )/(sin (A//2)) = (sin 60^(@))/(sin 30^(@)) = sqrt(3)`.