JEE Main 2021PhysicsWave OpticsMediumNumerical

JEE Main 2021 — Wave Optics Question with Solution

JEE Main 2021 (24 Feb Shift 1)

Question

An unpolarized 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

Assuming initially axis of Polarizer and Analyzer are parallel

Now emerging intensity =I02cos230°

=100322=100×34=75

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About this question

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.