Q. Unpolarized light travels through $2$ linear polarizers. What (minimum) angle should the second polarizer be relative to the first polarizer (the difference between $\text{\theta }_{1}$ and $\text{\theta }_{2}$ ) so that the final intensity of light is $3/8^{\text{th }}$ of the original value?

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A

$\frac{\pi }{3}$

B

$\frac{\pi }{6}$

C

$\frac{\pi }{4}$

D

$\frac{\pi }{2}$

Solution:

$\frac{3}{8}I_{0}=I=\frac{I_{0}}{2}cos^{2}\theta $

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