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Question
A horizontal wire 20 m long extending from east to west is falling with a velocity of 10 m/s normal to the Earth’s magnetic field of 0.5 × 10−4 T. What is the value of induced emf in the wire?
Solution
Data: l = 20 m, v = 10 m/s, B = 0.5 × 10−4 T
The magnitude of the induced emf,
|e| = Blv = (0.5 × 10−4)(20)(10) = 10-2 V = 10 mV
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