JEE Main 2015 — Electrostatics Question with Solution
JEE Main 2015 (10 Apr Online)
Question
A thin disc of radius has a concentric hole of radius in it (see figure). It carries uniform surface charge on it. If the electric field on its axis at a height from its centre is given as then the value of is
Choose an option
Show full solutionCorrect option: A
Correct answer
A
Step-by-step explanation
At the axial point of a uniformly charged disc electric field is given by,
By superposition principle, when inner disc is removed , then, electric field due to remaining disc is,
and b.
.
By superposition principle, when inner disc is removed , then, electric field due to remaining disc is,
and b.
.
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This is a previous-year question from JEE Main 2015, 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.