Question

Two Nicol prism are first crossed and then one of them is rotated through 30${}^0$. The percentage of the incident unpolarized light transmitted is

• A. 37.5
• B. 50
• C. 30
• D. 27

Answer 1

The correct option is A 37.5

REF.Image.

The final arrangement of prism is as follows :-

transmitted intensity in $I_2$.

unpolarized right of intensity I becomes half after crossing A

$\Rightarrow I_1=I/2$

and as $I_1$ passes B, it follows mauns law:-

$I_2=I_{1}co{s}^2\theta (\theta ={30}^{\circ })$

$\Rightarrow I_2=\frac{I}{2}co{s}^2\left({30}^{\circ }\right)=\frac{3I}{8}$

$\Rightarrow \frac{I_2}{I}=\frac{3}{8}=37.5$ % (Rqed)