If a reflected ray in air at an angle of reflection of 60$^{\circ}$is totally polarized,what is the index of refraction of the reflecting material?
A) 1.50
B) 2.00
C) 1.73
D) 1.15
E) this angle is not possible for an incident ray in air

Question

Quizplus · Accepted Answer

If a reflected ray is totally polarized, then the incident ray must be at the Brewster's angle. The Brewster's angle is given by the equation tanθB=n, where θB is the Brewster's angle and n is the refractive index of the reflecting material. Substituting the given angle 60°, we get tanθB=√3. The closest value of the refractive index that satisfies this equation is n=1.73, which corresponds to option C.

If a Reflected Ray in Air at an Angle of Reflection