Average induced EMF is given by, ϵ=N(tΔϕ)
Also, change in flux Δϕ=(ΔB)A
Given: Bi=5000T,
Bf=3000T
d=0.02m⇒r=2d=0.01m
Hence,
Δϕ=(ΔB)A
=(2000)π(0.01)2=0.2π
EMF, ϵ=N(tΔϕ)⇒22=N(20.2π)
⇒N=70
JEE Main 2024 — Physics Electromagnetism
A coil is placed perpendicular to a magnetic field of 5000T. When the field is changed to 3000T in 2s, an induced emf of 22V is produced in the coil. If the diameter of the coil is 0.02m, then the number of turns in the coil is:
Held on 31 Jan 2024 · Verified 6 Jul 2026.
7
70
35
140
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