Question

Unpolarised light of intensity $I_0$, is passed through a polarizer. What is the intensity of the transmitted light ?

• A. $I_0{\cos }^2\theta$
• B. $2I_0{\cos }^2\theta$
• C. $I_0{\cos }^2\theta /2$
• D. $2I_0{\cos }^2\theta 2$

Answer 1

The correct option is A $I_0{\cos }^2\theta$

The intensity $I$ is of an electromagnetic wave is directly proportional to square of the magnitude of electric field vector.

Therefore,

When unpolarised light having intensity is passed through a polarizer then intensity of light is,

$I_p=I_0{cos}^2\theta$

Correct option is A.