Halliday, Resnick & Walker — Electromagnetic Waves: Problem 60

60 In Fig. 33-51a, a light ray in water is incident at angle \(\theta_1\) on a boundary with an underlying material, into which some of the light refracts. There are two choices of underlying material. For each, the angle of refraction \(\theta_2\) versus the incident angle \(\theta_1\) is given in Fig. 33-51b. The vertical axis scale is set by \(\theta_{2s} = 80^\circ\). Without calculation, determine whether the index of refraction of (a) material 1 and (b) material 2 is greater or less than the index of water (\(n = 1.33\)). What is the index of refraction of (c) material 1 and (d) material 2?