Two polaroids are kept crossed to each other. Now one of them is rotated through an angle of `45^(@)` . The percentage of incident light now transmitted through the system is

Options

A. 0.15
B. 0.25
C. 0.5
D. 0.6

Answer

C

Explanation

Applying the law of Malus, we have
`l=l_(0)cos^(2)theta=l_(0)cos^(2)45^(@)`
`=l_(0)(1/(sqrt(2)))^(2)=(l_(0))/2`
I.e. 50% of incident light, now transmitted through the system.