Unpolarised light is passed through three successive Polaroid filters, each with its transmission axis at 45.0$\degree$ to the preceding filter.What percentage of light gets through?
A)0%
B)12.5%
C)25.0%
D)50.0%
E)33.3%

Question

Quizplus · Accepted Answer

When unpolarized light passes through the first Polaroid, its intensity is reduced by half. Each subsequent Polaroid, at 45 degrees to the previous one, reduces the intensity by another factor of cos²(45°) = 0.5. Therefore, the final intensity is (0.5) * (0.5) * (0.5) = 0.125 or 12.5% of the original intensity.

Unpolarised Light Is Passed Through Three Successive Polaroid Filters, Each °\degree°

Unpolarised Light Is Passed Through Three Successive Polaroid Filters, Each $\degree$