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^{\circ} to the pass axis of P_{3}. When a beam of unpolarized light of intensity I_{o} is incident on P_{1}, the intensity of light transmitted by the three polarizers is I. The ratio (I_{o}/I) equal (nearly):

 

 

  • Option 1)

    5.33

  • Option 2)

    16.00

  • Option 3)

    10.67

  • Option 4)

    1.80

 

Answers (1)
S solutionqc

 

Malus Law -

I= I_{0}\cdot \cos ^{2}\theta

\theta = angle made by E vector with transmission axis.

- wherein

I= Intensity of transmitted light after polarisation .

I_{0}= Intensity of  incident light.

 

 

the intensity of light transmitted from P_{1}=\frac{I_{o}}{2}

the intensity of light transmitted from P_{2}=\frac{I_{o}}{2}\cos ^{2}30=\frac{3I_{o}}{8}

The intensity of light transmitted from P_{3} 

I=\frac{3I_{o}\cos ^{2}60}{8}=\frac{3I_{o}}{32}

\frac{I_{o}}{I}=\frac{32}{3}=10.67

 


Option 1)

5.33

Option 2)

16.00

Option 3)

10.67

Option 4)

1.80

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