Question

A prism is made of glass of unknown refractive index. A parallel beam of light is incident on a face of the prism. The angle of minimum deviation is measured to be 40°. What is the refractive index of the material of the prism? The refracting angle of the prism is 60°. If the prism is placed in water (refractive index 1.33), predict the new angle of minimum deviation of a parallel beam of light.

Answer 1

The angle of minimum deviation, d_m = 40° A = 60°, µ = ?

When the prism is placed in water, µ_wa = 1.33, µ_ga = 1.53

(where D_m is the angle of minimum deviation of the prism in the water)