JEE Main 2020 — Electromagnetic Induction Question with Solution
From: JEE Main 2020 (Online) 7th January Morning Slot
Question
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 :
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 :
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(t) = I0t(1 - t)
We know, = BA
= 0nIA
= 0nAI0(t - t2)
Also VR =
= - 0nAI0(1 - 2t)
VR = 0 when 1 - 2t = 0
t = 0.5
Also we know, VR = IRr
IR =
after t = 0.5, IR reverses its direction.
We know, = BA
= 0nIA
= 0nAI0(t - t2)
Also VR =
= - 0nAI0(1 - 2t)
VR = 0 when 1 - 2t = 0
t = 0.5
Also we know, VR = IRr
IR =
after t = 0.5, IR reverses its direction.
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