SP212
Lesson 34
Ch 33.6-33.73 Total internal reflection and polarization by reflection
Problem 1
A flat piece of glass (with index of refraction 1.50) has a layer of ethanol (with index of refraction 1.36)
floating on top of it. Light traveling in the glass strikes the glass-ethanol surface. What is the critical angle
for total internal reflection in the glass?
Problem 2
A blinking light sits at the bottom of a swimming pool that is 2.00 m deep. How far horizontally can a
person in a boat at the surface move away from the light before the light is no longer visible? The index of
refraction of water is n=1.33, and that of air is n=1.00.
HINT: What is the angle at which no rays from the blinking light can make it out into the air?
Problem 3
Light traveling through air (n = 1) is incident on glass (n = 1.5) and the reflected beam is completely
polarized.
(a) What was the angle of incidence (θ1 )?
(b) What is the angle of refraction in the glass (θ2 )?