JEE Main 2020PhysicsWave OpticsEasyNumerical

JEE Main 2020 — Wave Optics Question with Solution

JEE Main 2020 (09 Jan Shift 2)

Question

In a Young's double slit experiment 15 fringes are observed on a small portion of the screen when light of wavelength 500 nm is used. Ten fringes are observed on the same section of the screen when another light source of wavelength λ is used. Then the value of λ is (in nm ) __________.

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Show full solutionCorrect answer: 750
Correct answer
750

Step-by-step explanation

15×500×Dd=10×λ2×Dd
λ2=15×50 nm
λ2=750 nm

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About this question

This is a previous-year question from JEE Main 2020, 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.