An innovative physics professor conducts laboratory exercises in the college swimming pool. The professor places a submersible laser under water (n = 1.33) and aims the beam horizontally toward the vertically oriented transparent polycarbonate side wall of the pool. The laser is shone on the pool wall at an angle of incidence of 42 degrees with respect to the normal, and at that angle the reflected ray is found to be completely polarized. What is the index of refraction of the polycarbonate side wall?
A) 1.11
B) 1.28
C) 1.20
D) 1.48

Question

Quizplus · Accepted Answer

The angle of incidence for which the reflected ray is completely polarized is called Brewster's angle. At Brewster's angle, the reflected and refracted rays are perpendicular to each other. Using Snell's law and the condition for Brewster's angle, we can find the index of refraction of the polycarbonate side wall.

An Innovative Physics Professor Conducts Laboratory Exercises in the College