JEE Main 2020PhysicsDual Nature of MatterHardMCQ

JEE Main 2020 — Dual Nature of Matter Question with Solution

JEE Main 2020 (08 Jan Shift 2)

Question

An electron (mass m ) with initial velocity v→=v0i^+v0j^ is in an electric filed E→=-E0k^. If λ0 is initial de-Broglie wavelength of electron, its de-Broglie wave length at time t is given by:

Choose an option

Show full solutionCorrect option: C
Correct answer
Cλ01+e2E2t22m2v02

Step-by-step explanation

Initial velocity of electron, 

v=v0i^+v0j^⇒u=v02+v02=v02

Initial de Broglie wavelength associated with electron, 

λ0=hp=hmv02

now,

v=u+at
Velocity as a function of time =v0i^+v0j^+eE0mtk^
so wavelength λ=hm2v02+e2E02m2t2
λ=λ01+e2E022m2v02t2

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About this question

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