Question

A polaroid \(P\) is placed between two crossed polaroids \(Q\) and \(R\) such that when unpolarised light is incident on \(Q\), it emerges from \(R\) with maximum possible intensity. The ratio of intensity of unpolarized light incident on \(P\) and the intensity of polarized light emerging from \(R\) is

• A. \(4:1\)
• B. \(2:1\)
• C. \(3:1\)
• D. \(1:1\)

Hint:

For crossed polaroids, maximum transmission is obtained when the middle polaroid is placed at \[ \boxed{45^\circ} \] to both. Apply Malus' law successively: \[ \boxed{I=I_0\cos^2\theta.} \]

Answer 1

The Correct Option is A