JEE Mains · Physics · STD 12 - 10. Wave optics
A beam of unpolarised light of intensity \(I_0\) is passed through a polaroid \(A\) and then through another polaroid \(B\) which is oriented so that its principal plane makes an angle of \(45^o \) relative to that of \(A\). The intensity of the emergent light is _______.
- A \(\;\frac{{I_o}}{8}\)
- B \(\;I_o\)
- C \(\;\frac{{I_o}}{2}\)
- D \(\;\frac{{I_o}}{4}\)
Answer & Solution
Correct Answer
(D) \(\;\frac{{I_o}}{4}\)
Step-by-step Solution
Detailed explanation
Relation between intensities \(I_{r}=\left(\frac{I_{0}}{2}\right) \cos ^{2}\left(45^{\circ}\right)=\frac{I_{0}}{2} \times \frac{1}{2}=\frac{I_{0}}{4}\)
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