JEE Main 2021PhysicsElectrostaticsMediumNumerical

JEE Main 2021 — Electrostatics Question with Solution

JEE Main 2021 (26 Feb Shift 2)

Question

27 similar drops of mercury are maintained at 10 V each. All these spherical drops combine into a single big drop. The potential energy of the bigger drop is ___________ times that of a smaller drop.

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Show full solutionCorrect answer: 243
Correct answer
243

Step-by-step explanation

2743πr3=43πR3

R=3r

Potential energy of smaller drop U1=35kq2r

Potential energy of bigger drop : U=35kQ2R

U=35k27q2R

U=35k2727q23r

U=2727335kq2r

U=243U1

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About this question

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.