JEE Main 2020PhysicsAlternating CurrentMediumMCQ

JEE Main 2020 — Alternating Current Question with Solution

JEE Main 2020 (04 Sep Shift 2)

Question

A series L-R circuit is connected to a battery of emf V. If the circuit is switched on at t=0, then the time at which the energy stored in the inductor reaches 1n times of its maximum value, is :

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Show full solutionCorrect option: A
Correct answer
ALRlnnn-1

Step-by-step explanation

Potential energy stored in inductor is given by U=12L2

∪∝l2

UU0=1I02

1n=1I02

1I0=1-e-RT/L=1n

t=LRlnnn-1  

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About this question

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