JEE Main 2021PhysicsWave OpticsEasyNumerical

JEE Main 2021 — Wave Optics Question with Solution

JEE Main 2021 (16 Mar Shift 1)

Question

A fringe width of 6 mm was produced for two slits separated by 1 mm apart. The screen is placed 10 m away. The wavelength of light used is x nm. The value of x to the nearest integer is ______.

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Show full solutionCorrect answer: 600
Correct answer
600

Step-by-step explanation

β=λDd

λ=βdD

λ=6×10-3×10-310

λ=6×10-7 m=600×10-9 m

λ=600 nm

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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.