An optical fiber is made of clear plastic with index of refraction n = 1.50 . For what angles with the surface will light remain within the plastic guide?
a. j < 66.6
c. j < 51.7
b. j < 41.8
d. j < 57.1
Question 2
Dmitri places one end of a copper rod in a heat reservoir and the other end in a heat sink. By what factor is the rate of heat flow changed when the temperature difference between the reservoir and sink is doubled?
a. 2.0
c. 4.0
b. 1/2
d. 1/4