Question

When two Polaroid sheets are crossed perpendicular to each other:

• A. Light gets completely transmitted
• B. Light gets completely extinguished
• C. Light causes harm to the human eye
• D. Alternate bright and dark bands can be seen

Answer 1

The correct option is B Light gets completely extinguished

When two polaroid sheets are pendicular then the angle between them is ${90}^0$.
$I=I_{0}co{s}^2\theta$
As cos $\theta$ becomes zero at $\theta ={90}^0$
Thus Intensity gets extinguished.