JEE Main 2021PhysicsAlternating CurrentMediumMCQ

JEE Main 2021 — Alternating Current Question with Solution

JEE Main 2021 (18 Mar Shift 2)

Question

The time taken for the magnetic energy to reach 25% of its maximum value, when a solenoid of resistance R, inductance L is connected to a battery, is :

Choose an option

Show full solutionCorrect option: C
Correct answer
CLRln2

Step-by-step explanation

Magnetic energy =12Li2=25%

ME⇒25%⇒i=i02

i=i01-R-Rt/L for charging

t=LRln2

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About this question

This is a previous-year question from JEE Main 2021, 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.