Question

A ray of light propagates in air, entering a rectangular quartz prism with index of refraction 1.66 at an incidence angle of 72⁰. After it passes through the quartz, it enters a fluid with index of refraction 1.33.

(a) What is the refracted angle when the light enters the quartz? ⁰

(b) What is refracted angle of the light when it enters the fluid? ⁰

(c) How much does the light speed up when it enters the fluid? m/s

Answer 1

yo h=1 1.60 ng 1.33 nar Using snell's law on surface AB is. n sin = n, sin (1.0)sin 72° = (1.66 )sin ? (1.0) sin 72° sin = (1.66 = 34.95 (b) The surface CD is, (1.66 )sin 34.95° = 1.33sin - (1.66 sin 34.950 1.33 = 45.64° (c) The velocity in fluid is, V=- 3x108 1.33 = 2.26×108 m/s The velocity in prism is, 3x108 1.66 = 1.81x10 m/s The velocity is, Av = 2.26x108 +1.81x108 = 4.1x10 m/s