JEE Main 2018PhysicsElectrostaticsMediumMCQ

JEE Main 2018 — Electrostatics Question with Solution

JEE Main 2018 (08 Apr)

Question

Three concentric metal shells A, B and C of respective radii a, b and c (a < b < c) have surface charge densities  +σ, -σ  and +σ respectively. The potential of shell B  is:

Choose an option

Show full solutionCorrect option: C
Correct answer
Cσε0a2-b2b+c

Step-by-step explanation



Net potential at B is due to the superposition of potential due to all shells, 

∨B=∨BI+∨BII+∨BIII

=K4πa2σb+K4πb2-σb+K4πc2σc

Required potential of b

=σa2ε0b-σb2ε0b+σc2ε0c

=σε0a2-b2b+c

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About this question

This is a previous-year question from JEE Main 2018, 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.