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A transformer has 100 turns in its primary coil and 200 turns in its secondary coil. If the primary is supplied with 120 V AC and carries a current of 10 A, what are the voltage and current in the secondary coil?
- 240 V, 5 A
- 240 V, 10 A
- 60 V, 20 A
- 120 V, 20 A
Correct answer: 240 V, 5 A
Solution
Vs = Vp * (Ns/Np) = 120 * (200/100) = 240 V. Power conserved so Is = Ip * (Np/Ns) = 10 * (100/200) = 5 A. Answer: 240 V, 5 A.
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