JEE Main 2021 — Wave Optics Question with Solution
From: JEE Main 2021 (Online) 24th February Morning Shift
Question
An unpolarised light beam is incident on the polarizer of a polarization experiment and the intensity of light beam emerging from the analyzer is measured as 100 Lumens. Now, if the analyzer is rotated around the horizontal axis (direction of light) by 30 in clockwise direction, the intensity of emerging light will be _________ Lumens.
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Show full solutionCorrect answer: 75
Correct answer
75
Step-by-step explanation
Given, I0 = 100 lumens
When analyser is rotated through an angle , the intensity of light will becomes
I = I0 cos2 = 100 cos230
= 100 = 75 lumens
When analyser is rotated through an angle , the intensity of light will becomes
I = I0 cos2 = 100 cos230
= 100 = 75 lumens
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This is a previous-year question from JEE Main 2021, covering the Wave Optics chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.