JEE Mains · Physics · STD 12 - 10. Wave optics
Unpolarized light of intensity \(I\) is incident on a system of two polarizers, \(A\) followed by \(B.\) The intensity of emergent light is \(I/2.\) If a third polarizer \(C\) is placed between \(A\) and \(B,\) the intensity of emergent light is reduced to \(I/3 .\) The angle between the polarizers \(A\) and \(C\) is \(\theta \) . Then
- A \(\cos \,\,\theta \, = \,{\left( {\frac{2}{3}} \right)^{1/4}}\)
- B \(\cos \,\,\theta \, = \,{\left( {\frac{1}{3}} \right)^{1/4}}\)
- C \(\cos \,\,\theta \, = \,{\left( {\frac{1}{3}} \right)^{1/2}}\)
- D \(\cos \,\,\theta \, = \,{\left( {\frac{2}{3}} \right)^{1/2}}\)
Answer & Solution
Correct Answer
(A) \(\cos \,\,\theta \, = \,{\left( {\frac{2}{3}} \right)^{1/4}}\)
Step-by-step Solution
Detailed explanation
Polariser \(A\) and \(B\) have same alignment of transmission axis. Lets assume polariser \(C\) is introduced at \(\theta \) angle \(\frac{1}{2}{\cos ^2}\,\theta \, \times {\cos ^2}\,\theta \, = \,\frac{1}{3}\) or,…
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