MCQ
Unpolarized light falls on two polarizing sheets placed one after another. What should be the angle between pass axis of the sheets so that final transmitted light have one fourth intensity of incident light?
  • A
    $30^o$
  • B
    $0^o$
  • C
    $60^o$
  • None of these

Answer

Correct option: D.
None of these
d
After passing through first $I$ $=\frac{I_{0}}{2}$

$\frac{I_{0}}{4}=\frac{I_{0}}{2} \cos ^{2} \phi$

$\Rightarrow \cos ^{2} \phi=\frac{1}{2}$

$\cos \phi=\frac{1}{\sqrt{2}}$

$\Rightarrow \phi=45^{\circ}$

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