Miscellaneous: Practice Problem & Solution
A beam of unpolarised light of intensity \(I_0\) is passed through a polaroid \(A\) and then through analyser \(B\) which is oriented such that its pass-axis makes an angle of \(30^\circ\) relative to that of \(A\). The intensity of emergent light is
Solution Explained:
To solve this problem, we apply the core principles of Miscellaneous. Understanding the underlying formula is key to arriving at the correct answer below:
Intensity after polaroid \(A\) is \(I_1 = frac{I_0}{2}\). Using Malus's Law, the intensity after analyser \(B\) is \(I_2 = I_1 \cos^2 30^\circ = frac{I_0}{2} \left(\frac{\sqrt{3}}{2}\right)^2 = frac{3I_0}{8}\).
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