JEE Main 2020PhysicsCapacitanceEasyNumerical

JEE Main 2020 — Capacitance Question with Solution

JEE Main 2020 (06 Sep Shift 1)

Question

Suppose that intensity of a laser is 315π W m-2. The rms electric field, in units of V m-1 associated with this source is close to the nearest integer is -ε0=8.86×10-12 C2 N m-2; c=3×108 m s-1

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Show full solutionCorrect answer: 275
Correct answer
275

Step-by-step explanation

12C∈0Ems2=315π

Erms=315×2π×3×108×8.86×10-12

=63083.4612×10-4

=7.5484×104

=2.75×102=2.75×102=275

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About this question

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