JEE Main 2021PhysicsWave OpticsHuygens Principle And Interference Of LighteasyNumerical

JEE Main 2021Wave Optics Question with Solution

From: JEE Main 2021 (Online) 16th March Morning Shift

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

= 6 mm, d = 1 mm, D = 10 m

= ?

We know,

6 103 =

=

= 600 109 m

= 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.