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A transformer has 50 turns in its primary winding and 1500 turns in its secondary winding. If the magnetic flux linked with the primary is expressed as φ = φ0 + 4t, where φ is in webers, t is in seconds, and φ0 is a constant, what is the induced voltage across the secondary winding?
- 120 volts
- 220 volts
- 30 volts
- 90 volts
Correct answer: 120 volts
Solution
The induced voltage in a transformer is proportional to the turns ratio and the rate of change of magnetic flux. Given the turns ratio of 1500 to 50, which is 30, and the rate of change of flux is 4 webers per second, the induced voltage in the secondary is calculated as 30 times 4, resulting in 120 volts.
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