A light ray strikes the surface of sapphire (n = 1.77) at an angle of incidence of 40.0°. What angle of refraction results?
A) 21.3°
B) 50.0°
C) 59.7°
D) 57.0°
E) 17.7°

Question

Quizplus · Accepted Answer

Using Snell's Law, $n_1 \sin(\theta_1) = n_2 \sin(\theta_2)$, where $n_1$ is the refractive index of the first medium (air, assuming $n_1 = 1$), $\theta_1$ is the angle of incidence, $n_2$ is the refractive index of the second medium (sapphire, $n_2 = 1.77$), and $\theta_2$ is the angle of refraction. Solving for $\theta_2$, we get $\theta_2 = \sin^{-1}\left(\frac{n_1}{n_2} \sin(\theta_1)\right) = \sin^{-1}\left(\frac{1}{1.77} \sin(40.0°)\right) \approx 21.3°$.

A Light Ray Strikes the Surface of Sapphire (N =