Find the magnitude of the average induced emf in the coil when the magnet is turned off and the field decreases to 0 T in 2.8 s
1 answer:
Answer:
<em>2.15 mV</em>
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Explanation:
The complete question is
You have a coil of wire with 17 turns each of 1.5 cm radius. You place the plane of the coil perpendicular to a 0.50-TB? field produced by the poles of an electromagnet.
Find the magnitude of the average induced emf in the coil when the magnet is turned off and the field decreases to 0 T in 1.9 s .
Radius of the coil = 1.5 cm = 0.015 m
number of turns = 17
Initial magnetic field = 0.50 T
Final magnetic field = 0 T
time taken dt = 1.9 s
Area pf the coil = π = 3.142 x
= 7.1 x 10^-4 m^2
magnetic flux = BA
initial flux = A = 0.5 x 7.1 x 10^-4 = 3.55 x 10^-4 Wb
Final flux = A = 0 x 7.1 x 10^-4 = 0 Wb
change in flux dФ = 3.55 x 10^-4 - 0 = 3.55 x 10^-4 Wb
Induced EMF E = NdФ/dt = (17 x 3.55 x 10^-4)/2.8 = 2.15 x 10^-3 V
==> <em>2.15 mV</em>
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