JEE Mains · Physics · STD 12 - 10. Wave optics
An unpolarised light beam of intensity \(2 I _{0}\) is passed through a polaroid \(P\) and then through another polaroid \(Q\) which is oriented in such a way that its passing axis makes an angle of \(30^{\circ}\) relative to that of \(P\). The intensity of the emergent light is.
- A \(\frac{I_{0}}{4}\)
- B \(\frac{I_{0}}{2}\)
- C \(\frac{3 I_{0}}{4}\)
- D \(\frac{3 I_{0}}{2}\)
Answer & Solution
Correct Answer
(C) \(\frac{3 I_{0}}{4}\)
Step-by-step Solution
Detailed explanation
\(I _{1}=\frac{1}{2}\left(2 I _{0}\right)= I _{0}\) \(I _{2}= I _{1} \cos ^{2} 30^{\circ}\) \(= I _{0} \cdot \frac{3}{4}=\frac{3 I _{0}}{4}\)
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