JEE Main 2020 — Electromagnetic Induction Question with Solution
From: JEE Main 2020 (Online) 7th January Evening Slot
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 10 s 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: D
Correct answer
D2.5 s and 5.0 s
Step-by-step explanation
Flux = = BAcost
Induced emf = e = = -BA(-)sint
= BAsint
e will be maximum at t = ,
= ,
t = or i.e. 2.5 s or 7.5 s.
For induced emf to be minimum i.e zero.
= n
t =
Induced emf is zero at t = 5 s, 10 s
Induced emf = e = = -BA(-)sint
= BAsint
e will be maximum at t = ,
= ,
t = or i.e. 2.5 s or 7.5 s.
For induced emf to be minimum i.e zero.
= n
t =
Induced emf is zero at t = 5 s, 10 s
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