A beam of light consisting of red, green and blue colours is incident on right angled prism. The refractive indices of the material of the prism for the above red, green and blue wavelengths are `1.39,1.44 and 1.47` respectively. The prism will.
.

Options

A. separate part of the red colour from the green and blue colours
B. separate part of the blue colour from the red and green colours
C. separate all the three colours from one another
D. not separate even partially any colour from the other two colours.

Answer

A

Explanation

(a) For total internal reflection `mu=(1)/(sinC)=(1)/(sin45degree)=1.414`
i.e. for an angle of incidence of `45degrees`, that colour will suffer total internal reflection for which the refractive index is less than 1.414.
Therefore, red light will be refracted at interface AB whereas blue and green light will suffer total internal reflection.