Flux: ϕ=BA=sin(100t) Wb
Induced EMF: ε=−dtdϕ=−100cos(100t) V
Induced current: I=Rε=−cos(100t) A
Power dissipated: P=I2R=100cos2(100t) W
Average power: Pavg=21×100=50 W
Time period: T=1002π s
Energy in one period: E=Pavg×T=50×1002π=π J
JEE Main 2026 — Physics Electromagnetism
A conducting circular loop of area 1.0 m2 is placed perpendicular to a magnetic field which varies as B=sin(100t) Tesla. If the resistance of the loop is 100Ω, then the average thermal energy dissipated in the loop in one period is ____ J.
Held on 21 Jan 2026 · Verified 6 Jul 2026.
π2
π
2π
2π
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