After the class is over you take a journey to a tropical oasis to get some rest
ID: 1477587 • Letter: A
Question
After the class is over you take a journey to a tropical oasis to get some rest and relaxation. While staring at the sunset, you notice that the reflection of the sun off the surface of the water (which you can approximate as flat) is slowly disappearing from your view. Then you remember, your totally fly and not hastily drawn on sunglasses are linearly polarized. So...
a) What intensity of direct sunlight passes through your glasses? Assume direct sunlight has an intensity of I_D.
b) For your glasses to completely cut the reflection of the sun off the surface of the water, how must their axis of polarization be oriented relative to the surface of the water? Circle one:
Perpendicular // 45° // Horizontal
c) At what angle above the horizon will the sun be when the reflection totally disappears from your sight, i.e. will it be totally linearly polarized and blocked by properly made glasses? Air has n = 1.00, water has n = 1.33.
d) If your glasses are tilted at an angle of 60° relative to the polarization of the reflected light, what intensity will pass through? Assume the reflected/polarized sunlight off the water has intensity I_R.
Explanation / Answer
a) I_D/2
B) SHOULD BE PERPENDICULAR I.E. AT 90 DEGREES,
C)tan-1(1.33/1) = 53.06 degrees (Brewster's Law)
d)I_R COS^2 (60) =1/4*(I_R) = 0.25* I_R (MALUS LAW)