Chapter 33, Problem 60P

In Fig. 33-58, light from ray A refracts from material 1 (n₁ = 1.60) into a thin layer of material 2 (n₂ = 1.80), crosses that layer, and is then incident at the critical angle on the interface between materials 2 and 3 (n₂= 130), (a) What is the value of incident angle θ_A? (b) If θ_A is decreased, does part of the light refract into material 3?

Figure 33-58 Problem 60.

Light from ray B refracts from material l into the thin layer, crosses that layer, and is then incident at the critical angle on the interface between materials 2 and 3. (c) What is the value of incident angle θ_B? (d) If θ_B is decreased, does part of the light refract into material 3?