JEE Main 2018PhysicsDual Nature of MatterMediumMCQ

JEE Main 2018Dual Nature of Matter Question with Solution

JEE Main 2018 (15 Apr)

Question

Two electrons are moving with non-relativistic speeds perpendicular to each other. If corresponding de brogile wavelengths are λ1 and λ2, their de brogile wavelength in the frame of reference attached to their centre of mass is:

Choose an option

Show full solutionCorrect option: B
Correct answer
BλCM=2λ1λ2λ12+λ22

Step-by-step explanation

Momentum of each electron hλ1 i^ and hλ2j^

Velocity of centre of mass

Vcm=h2mλ1 i^+h2mλ2j^

Velocity of 1st particle about centre of mass

Vcm=h2mλ1 i^-h2mλ2j^

λcm=hh24λ12+h24λ22=2λ1 λ2λ12+λ22

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About this question

This is a previous-year question from JEE Main 2018, covering the Dual Nature of Matter 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.