A system of three polarizers P _ 1 , P _ 2 , P _ 3 is set up such that the pass axis of P _ 3 is crossed with respect to that of P _ 1 . The pass axis of P _ 2 is inclined at 60 ^ o to the pass axis of P _ 3 . When a

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Correct answer: D. 10.67

A system of three polarizers P _ 1 , P _ 2 , P _ 3 is set up such that the pass axis of P _ 3 is crossed with respect

The intensity of light coming out of 1st Polaroid will be

{I}_{1} = \dfrac{{I}_{0}}{2}

From Malus law

I = {I}_{0}\cos^{2} \theta

From Polaroid 2:

I = \dfrac{{I}_{0}}{2}\cos^{2} 30 ° = \dfrac{{I}_{0}}{2}{\left(\dfrac{\sqrt{3}}{2}\right)}^{2} = \dfrac{3{I}_{0}}{8}

From Polaroid 3:

I = \dfrac{3{I}_{0}}{8}\cos^{2} 60 ° = \dfrac{3{I}_{0}}{8}{\left(\dfrac{1}{2}\right)}^{2} = \dfrac{3{I}_{0}}{32}

Now,

\dfrac{{I}_{0}}{I} = \dfrac{32}{3} = 10.67

A system of three polarizers P _ 1 , P _ 2 , P _ 3 is set up such...

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