Question

Unpolarized light falls on two polarizing sheets placed one on top of other. If the intensity of transmitted light is one fourth of the incident light, the angle between them is

• A. $30^{\circ}$
• B. $40^{\circ}$
• C. $45^{\circ}$
• D. $60^{\circ}$

Answer 1

Answer: (D)

From law of Malus $I=I_{0} \cos ^{2} \theta$
Given, $I=\frac{I_{0}}{4}$
$\frac{1}{4}=\cos ^{2} \theta$
$\Rightarrow \cos \theta=\frac{1}{2}$
$\Rightarrow \theta=60^{\circ}$