A rainbow is produced by the reflection of sunlight by spherical drops of water in the air. Figure 33.62 shows a ray that refracts into a drop at point A, is reflected from the back surface of the drop at point B, and refracts back into the air at point C. The angles of incidence and refraction, ?a and ?b, are shown at points A and C, and the angles of incidence and reflection, ?a and ?c are shown at point B.(a) Show that ?Ba = ?Ab, ?Ca = ?Ab, and ?Cb = ?Ab, ??(b) Show that the angle in radians between the ray before it enters the drop at A and after it exits at C (the total angular deflection of the ray) is ? = 2?Aa ?? 48Ab + ?.

d= 4(n = m2)