Two Polaroids P1 and P2 are placed with their axis perpendicular to each other. Unpolarised light I0 is incident on P1. A third polaroid P3 is kept in between P1 and P2 such that its axis makes an angle 45° with that of P1. The intensity of transmitted light through P2 is :-

Question

Two Polaroids P1 and P2 are placed with their axis perpendicular to each other. Unpolarised light I0 is incident on P1. A third polaroid P3 is kept in between P1 and P2 such that its axis makes an angle 45° with that of P1. The intensity of transmitted light through P2 is :- (A) (I0/4) (B) (I0/8) (C) (I0/16) (D) (I0/2)

Tardigrade Admin · Accepted Answer

<img class="img-fluid question-image" alt="Solution" src="https://cdn.tardigrade.in/q/nta/p-krmegnchr2o1axrk.jpg" /> I1=(I0/2) I2=(I0/2)cos245° =(I0/4) I3=(I0/4)cos245° =(I0/8)

$\frac{I _{0}}{4}$

$\frac{I _{0}}{8}$

$\frac{I _{0}}{16}$

$\frac{I _{0}}{2}$

$I_{1} = \frac{I _{0}}{2}$
$I_{2} = \frac{I _{0}}{2} co s^{2} 4 5^{\circ} = \frac{I _{0}}{4}$
$I_{3} = \frac{I _{0}}{4} co s^{2} 4 5^{\circ} = \frac{I _{0}}{8}$

4I0​​

8I0​​

16I0​​

2I0​​

I1​=2I0​​ I2​=2I0​​cos245∘=4I0​​ I3​=4I0​​cos245∘=8I0​​

$\frac{I _{0}}{4}$

$\frac{I _{0}}{8}$

$\frac{I _{0}}{16}$

$\frac{I _{0}}{2}$

$I_{1} = \frac{I _{0}}{2}$
$I_{2} = \frac{I _{0}}{2} co s^{2} 4 5^{\circ} = \frac{I _{0}}{4}$
$I_{3} = \frac{I _{0}}{4} co s^{2} 4 5^{\circ} = \frac{I _{0}}{8}$