JEE Main 2020PhysicsElectromagnetic InductionHardMCQ

JEE Main 2020 — Electromagnetic Induction Question with Solution

JEE Main 2020 (07 Jan Shift 2)

Question

A planar loop of wire rotates in a uniform magnetic field. Initially, at t=0 , the plane of the loop is perpendicular to the magnetic field. If it rotates with a period of 10s about an axis in its plane then the magnitude of induced emf will be maximum and minimum, respectively at:

Choose an option

Show full solutionCorrect option: B
Correct answer
B2.5 s and 5.0 s

Step-by-step explanation

Φ=B→·A →=BAcosθ =BAcosωt

e=dϕdt =BAωsinωt


When ωt=π2
∵ϕ will be minimum.
∴e will be maximum
t=π2π5=2.5 s

When ωt=π
∵ϕ will be maximum.
∴e will be minimum
t=ππ/5=5 s

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About this question

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