Radius =d/2=2mm
Rwire=Aρl
ϕ=BA;∣e∣=dtdϕ=dtdB(A)
i=Re=∣dtdB∣ρl(A)2=1.23×10−8×4×0.30.032×π×2×10−32
=0.61A
A uniform magnetic field B exists in a direction perpendicular to the plane of a square loop made of a metal wire. The wire has a diameter of 4mm and a total length of 30cm. The magnetic field changes with time at a steady rate dB/dt=0.032Ts−1. The induced current in the loopis close to (Resistivity of the metal wire is 1.23×10−8Ωm )
Held on 3 Sept 2020 · Verified 6 Jul 2026.
0.43 A
0.61 A
0.34 A
0.53 A
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