Answer to Question #343694 in Physics for Bbmmm

Question

Benzene has a refractive index of 1.43. Suppose a light ray strikes its

surface at an angle of 40°, what is the directions of the reflected and the

refracted rays?

Answer 1

The angle of reflection is equal to the angle of incidence, so

$$\theta_{\rm refl}=\theta_{\rm inc}=40^\circ$$

The Snell's law says

$$\sin\theta_{\rm inc} n_1=\sin\theta_{\rm refr}n_2$$

Hence, the angle of refraction

$$\theta_{\rm refr}=\sin^{-1}(\sin\theta_{\rm inc} n_1/n_2)$$

$$\theta_{\rm refr}=\sin^{-1}(\sin40^\circ* 1.00/1.43)\\ =26.7^\circ$$