I=I0t−I0t2
ϕ=BA
ϕ=μ0nIA
VR=−dtdϕ=−μ0nAI0(1−2t)
VR=0 at t=21
And IR=ResistanceofloopVR=0
JEE Main 2020 — Physics Electromagnetism
A long solenoid of radius R carries a time (t) dependent current I(t)=I0t(1−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 EMF(VR) in the ring change as:
Held on 7 Jan 2020 · Verified 6 Jul 2026.
Direction of IR remains unchanged and VR is maximum at t=0.5
At t=0.25 direction of IR reverses and VR is maximum
Direction of IR remains unchanged and VR is zero at t=0.25
At t=0.5 direction of IR reverses and VR is zero
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