JEE Main 2024PhysicsWave OpticsMediumNumerical

JEE Main 2024 — Wave Optics Question with Solution

JEE Main 2024 (31 Jan Shift 1)

Question

Two waves of intensity ratio 1 : 9 cross each other at a point. The resultant intensities at the point, when (a) Waves are incoherent is I1 b  Waves are coherent is I2 and differ in phase by 60o. If I1I2=10x, then x= _________.

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Show full solutionCorrect answer: 13
Correct answer
13

Step-by-step explanation

For incoherent wave, I1=IA+IB⇒I1=I0+9I0

⇒I1=10I0

For coherent wave I2=IA+IB+2IAIBcos60o

⇒I2=I0+9I0+29I02×12=13I0

⇒I1I2=1013

Therefore, x=13.

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About this question

This is a previous-year question from JEE Main 2024, 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.