Reflection and Refraction
In Fig. 33-52$a$, a beam of light in material 1 is incident on a boundary at an angle of $\theta_{1}=30^{\circ} .$ The extent of refraction of the light into material 2 depends, in part, on the index of refraction $n_{2}$ of material 2. Figure 33-52$b$ gives the angle of refraction $\theta_{2}$ versus $n_{2}$ for a range of possible $n_{2}$ values. The vertical axis scale is set by $\theta_{2 a}=20.0^{\circ}$ and $\theta_{2 b}=40.0^{\circ} .$ (a) What is the index of refraction of material 1$?$ (b) If the incident angle is changed to $60^{\circ}$ and material 2 has $n_{2}=2.4$ , then what is angle $\theta_{2} ?$