A beam of light consisting of red, green and blue colour is incident on a right angled prism. The refractive indices of the material of the prism for the above red, green and blue wavelength are 1.39, 1.44 and 1.47 respectively. The prism will
Answer & explanation
Correct answer: option 1
At face AB, i = 0. So, r = 0, i.e., no bending will take place. So, light beam will be incident on face AC at an angle 45°. The face AC will not transmit the light for which $i>\theta_C$, i.e., $\sin i>\sin \theta_C$
or $\sin 45^{\circ}>(1 / \mu)$ i.e., $\mu>\sqrt{2}(=1.41)$
Now as µR < µ while µG and µB > µ, so red will be transmitted through the face AC while green and blue will be reflected. So, the prism will separate red colour from green and blue.