A coil of 200 turns has its magnetic flux fall from 4.0 x 10^-3 Wb to zero in 0.020 s. What is the average induced emf?
Answer and explanation
Correct answer: D. 40 V
- Step 1: Faraday's law: . Step 2. V. Answer: 40 V. Why not the others: 0.20 V omits the number of turns; 1000 V inverts the time and flux; 0.80 V multiplies N by the flux without dividing by the time.
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