Question

If the light ray moves from inside the glass toward the glass-air interface at an angle of 35.0° to the normal, determine the angle of refraction. The ray bends ________° away from the normal, as expected.

Answer 1

The angle of refraction $\theta_2$ is given by the Snell's law:

$$\sin \theta_2 = \dfrac{n_1}{n_2}\sin\theta_1$$

where $\theta_1 = 35\degree$ is the angle of incidence, $n_1 = 1.52$ is the refractive ingex of glaass, $n_2 = 1$ is the refractive ingex of air. Thus

$$\sin \theta_2 = \dfrac{1.52}{1}\sin35\degree \approx 0.87\\ \theta_2 \approx \arcsin0.87 \approx 60.5\degree$$

Answer. The ray bends 60.5° away from the normal, as expected.