MCQ
An unpolarized light passes through three polarizing sheets whose polariging directions make an angle of $30^o$ , $60^o$ and $30^o$ with $y$ axis in same sense. What fraction of initial intensity is transmitted by the system ?
  • A
    $\frac {1}{2}$
  • $\frac {9}{32}$
  • C
    $\frac {3}{32}$
  • D
    $\frac {9}{64}$

Answer

Correct option: B.
$\frac {9}{32}$
b
$I = \frac{{{I_0}}}{2} \times {\cos ^2}{30^o} \times {\cos ^2}{30^o}$

= $\frac {9I_0}{32}$

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