Initially unpolarized light goes through two polarizers, first polarizer A and t
ID: 1451222 • Letter: I
Question
Initially unpolarized light goes through two polarizers, first polarizer A and then polarizer B. Both polarizers can be only oriented to an angle between 0° and 90°. The polarizer A is oriented at 38° from the vertical, and the polarizer B is oriented at 77° from the vertical.
(a) What percentage would be the light intensity in the region after the polarizer A and before the polarizer B compared with the intensity of the initial unpolarized light? _________%
(b) Find the intensity of the light after the polarizer B in terms of percentage compared with the intensity of the initial unpolarized light. ________%
Explanation / Answer
(a)
The intensity of light passing through the first polarizer is,
I1 = I0 / 2
I1 = 0.5 I0
I1/ I0 = 50 %
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(b)
The intensity of light passing through the first polarizer is,
I2 = I1 cos^(theta)
I2 = (I0/2) cos^2(77-38)
l2 = Io * (0.30)
I2/ I0 = 0.30
I2/ I0 = 30 %