A circular loop of wire with radius 0.0390 m and resistance 0.161 Ω is in a region of spatially uniform magnetic field. The magnetic field is directed out of the plane of the figure. The magnetic field has an initial value of 8.47 T and is decreasing at a rate of -0.645 T/s.
What is the rate at which electrical energy is being dissipated by the resistance of the loop?
1 Answer
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I assume the loop is in the plane of the “figure”.
Voltage V induced in loop = π ͯ 0.039² ͯ 0.645 = 3.08 /10³ volts
Power dissipation = V²/R where R is the loop resistance
= 3.08²/(0.161 ͯ 10^6) = 58.9 ͯ 10^-6 Watts.