Question

Horizontal rays of red light (λ = 660 nm, in vacuum) and violet light (λ = 410 nm, in vacuum) are incident on the flint-glass prism shown in the drawing. The indices of refraction for the red and violet light are nred = 1.662 and nviolet = 1.698. The prism is surrounded by air. What is the angle of refraction for each ray as it emerges from the prism? (Assume α = 22.8°.)