JEE Main 2020PhysicsMagnetic Effects of CurrentMediumMCQ

JEE Main 2020 — Magnetic Effects of Current Question with Solution

JEE Main 2020 (07 Jan Shift 1)

Question

A long solenoid of radius R carries a time t dependent current It=I0t1-t . A ring of radius 2R is placed coaxially near its middle. During the time interval 0≤t≤1, the induced current IR and the induced EMFVR in the ring change as:

Choose an option

Show full solutionCorrect option: D
Correct answer
DAt t=0.5 direction of IR reverses and VR is zero

Step-by-step explanation

I=I0t-I0t2
ϕ=BA
ϕ=μ0nIA
VR=-dϕdt=-μ0nAI01-2t
VR=0 at t=12
And IR=VRResistance of loop=0
 

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About this question

This is a previous-year question from JEE Main 2020, covering the Magnetic Effects of 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.