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The primary of a transformer has 100 turns and its secondary has 200 turns. If the ...

The primary of a transformer has 100 turns and its secondary has 200 turns. If the voltage at the primary is 100V, determine the voltage at the secondary.
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  • A 50V
  • B 100V
  • C 200V
  • D 400V
Correct Answer: Option C
Explanation:
The ideal transformer (either step-up or step-down) works with the equation:
\(\frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{p}} = \frac{I_{p}}{I_{s}}\)
where \(V_{s}\) and \(V_{p}\) are the voltages applied to the secondary and the primary respectively
\(N_{s}\) and \(N_{p}\) are the number of turns on the secondary and primary coils respectively
\(I_{p}\) and \(I_{s}\) are the currents flowing in the primary and secondary coils respectively.
\(\frac{V_{s}}{100} = \frac{200}{100}\)
\(V_{s} = \frac{200\times 100}{100} = 200V\)

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