JEE Main 2020PhysicsElectrostaticsHardMCQ

JEE Main 2020 — Electrostatics Question with Solution

JEE Main 2020 (02 Sep Shift 2)

Question

A charge Q is distributed over two concentric conducting thin spherical shells radii r and R R>r. If the surface charge densities on the two shells are equal, the electric potential at the common centre is : 

Choose an option

Show full solutionCorrect option: D
Correct answer
D14πϵ0(R+r)R2+r2Q

Step-by-step explanation

Q1=σ4πr2

Q2=σ4πr2

∴Q=σ4πr2+R2∴  σ=Q4πr2+R2

VC=KQ1r+KQ2R

=K04πr2r+K04πR2R

=KQ4π(r+R)4πr2+R2

=KQ(r+R)r2+R2

 

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About this question

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