An oil film floats on a water surface.The indices of refraction for water and oil,respectively,are 1.333 and 1.466.If a ray of light is incident on the air-to-oil surface at an angle of 37.0 $\degree$with the normal,what is the incident angle at the oil-to-water surface?
A)18.1 $\degree$
B)24.2 $\degree$
C)27.3 $\degree$
D)37.0 $\degree$

Question

Quizplus · Accepted Answer

We can use Snell's Law to solve this problem. The incident angle at the air-to-oil surface and the refractive indices of the two materials allow us to calculate the angle of refraction at this surface:
sin(37.0°) = (1.333/1.466)sin(refraction angle)
sin(refraction angle) ≈ 0.809
refraction angle ≈ 54.2°

This angle is now the incident angle at the oil-to-water surface. We can use Snell's Law again to find the angle of refraction in the water:
sin(54.2°) = (1.466/1.333)sin(refraction angle)
sin(refraction angle) ≈ 0.711
refraction angle ≈ 47.0°

Therefore, the incident angle at the oil-to-water surface is 47.0°, which is closest to choice B (24.2°).

An Oil Film Floats on a Water Surface °\degree° With the Normal,what Is the Incident Angle at the Oil-To-Water

An Oil Film Floats on a Water Surface $\degree$ With the Normal,what Is the Incident Angle at the Oil-To-Water