A layer of water (n = 1.333) floats on carbon tetrachloride (n = 1.461) contained in an aquarium. To the nearest degree, what is the critical angle at the interface between the two liquids?
A) 88°
B) 78°
C) 66°
D) 58°
E) 43°

Question

Quizplus · Accepted Answer

The critical angle can be calculated using Snell's Law: sin(θc) = n2/n1, where n1 is the refractive index of water and n2 is the refractive index of carbon tetrachloride. Thus, sin(θc) = 1.461/1.333. Solving for θc gives approximately 66°.

A Layer of Water (N = 1