The quantity that remains constant in a transformer is
Correct answer: D. power
- A. current
- B. voltage
- C. resistance
- D. power
Explanation
The power remains constant. This means that the power input to the primary coil is equal to the power output from the secondary coil, minus any losses due to inefficiency. The formula for power ((P)) is given by (P = VI), where (V) is voltage and (I) is current. So, if the voltage increases during the transformation, the current decreases proportionally, and vice versa, to keep the power constant. This is a consequence of the conservation of energy principle. Pprimary = Psecondary
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About Transformers
Transformers transfer alternating electrical energy between coils by mutual induction, with voltage ratio determined by the turns ratio. The topic covers step-up and step-down transformers, current changes, ideal power conservation and practical losses such as heating and flux leakage. A transformer requires changing magnetic flux, so it does not operate with steady direct current.
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