Two polaroids are in crossed situation and intensity of polarized light is zero. If third polaroid is placed in between such that it makes half angle with optic axis, than angle between two polaroids, then intensity of polarized light will be ....... Where `I_(0)` is maximum intensity of incident light.

Options

A. `(I_(0))/(2)`
B. `(I_(0))/(4)`
C. `I_(0)`
D. `(I_(0))/(8)`

Answer

D

Explanation

Intensity of incident light is `I_(0)` on first polaroid then it is `(I_(0))/(2)` for polarized light.
Now, intensity of incident light of secon polaroid is `I_(1)=I_(2)` hence intensity of polarize light from it,
`I..=(I_(1))/(2)cos^(2) theta`
`=(I_(0))/(4)cos^(2)45^(@)`
`=(I_(0))/(4)xx(1)/(sqrt((2)^(2)))=(I_(0))/(8)`