JEE Main 2021PhysicsWave OpticsMediumNumerical

JEE Main 2021Wave Optics Question with Solution

JEE Main 2021 (26 Aug Shift 2)

Question

A source of light is placed in front of a screen. The intensity of light on the screen is I. Two Polaroids P1 and P2 are so placed in between the source of light and screen that the intensity of light on the screen is I2. Then the P2, should be rotated by an angle of (degrees) so that the intensity of light on the screen becomes 3I8.

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Show full solutionCorrect answer: 30
Correct answer
30

Step-by-step explanation

Recall the law of Malus I'=I2cos2θ

Here θ is the angle between two polaroids, 

3I8=I2cos2θθ=30°.

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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.