63 In Fig. 33-60, light enters a 90° triangular prism at point P with inci- dent angle 6, and then some of it refracts at point Q with an angle of refraction of 90°. (a) What is the in- dex of refraction of the prism in terms of 6? (b) What, numerically, is the maximum value that the index of refraction can have? Does light emerge at Q if the incident angle at P is (c) increased slightly and (d) decreased slightly? Figure 33-60 Problem 63.

63 In Fig. 33-60, light enters a 90° triangular prism at point P with inci- dent angle 0, and then some of it refracts at point Q with an angle of refraction of 90°. (a) What is the in- dex of refraction of the prism in terms of 0? (b) What, numerically, Air Q Figure 33-60 Problem 63. is the maximum value that the index of refraction can have? Does light emerge at Q if the incident angle at P is (c) increased slightly and (d) decreased slightly?

77 E Rainbow. Figure 33-67 shows a light ray entering and then leaving a falling, spherical raindrop after one internal reflec- tion (see Fig. 33-21a). The final direction of travel is deviated (turned) from the initial direction of travel by angular deviation Bdev- (a) Show that 6sey is Odey = 180° + 20, – 48, where e, is the angle of incidence of the ray on the drop and 0, is the angle of refraction of the ray within the drop. (b) Using Snell's law, substitute for 6, in terms of 6, and the index of refraction n of the water. Then, on a graphing calculator or with a computer graphing package, graph Osey versus 0, for the range of possible 6; values and for n = 1.331 for red light (at one end of the visible spectrum) and n = 1.333 for blue light (at the other end). The red-light curve and the blue-light curve have different minima, which means that there is a different angle of minimum deviation for each color. The light of any given color that leaves the drop at that color's angle of…

A ray of light crosses the boundary between some substance with n = 1.54 and air, going from the substance into air. If the angle of incidence is 29◦ what is the angle of refraction?   Calculate to 1decimal.