JEE Main 2021 — Electrostatics Question with Solution
From: JEE Main 2021 (Online) 24th February Evening Shift
Question
Two electrons each are fixed at a distance '2d'. A third charge proton placed at the midpoint is displaced slightly by a distance x (x << d) perpendicular to the line joining the two fixed charges. Proton will execute simple harmonic motion having angular frequency : (m = mass of charged particle)
Choose an option
Show full solutionCorrect option: B
Correct answer
B
Step-by-step explanation
The arrangement of charges is shown below
As we know that,
Coulomb's force between two charges. i.e., q1 and q2,
..... (i)
Here,
Force in SHM, ...... (ii)
Since, in order to have SHM +q should move downwards and force responsible for this will be only
..... (iii)
Using Eqs. (ii) and (iii), we get
As,
As we know that,
Coulomb's force between two charges. i.e., q1 and q2,
..... (i)
Here,
Force in SHM, ...... (ii)
Since, in order to have SHM +q should move downwards and force responsible for this will be only
..... (iii)
Using Eqs. (ii) and (iii), we get
As,
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This is a previous-year question from JEE Main 2021, covering the Electrostatics 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.