Question

What should be the angle of incidence of a light ray incident through air on the boundary separating air from water so that the angle of refraction is 30 °? (The refractive index of air is 1 and that of water is 1.32) Use Snell's law 1 sin (i) = 1.32 sin 30°.

Answer 1

According to the suggested law, we have

$$1 \sin (i) = 1.32 \sin 30°,\\\space\\ i=\arcsin [1.32\sin30°]=41.3°.$$