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Question
What is the function of a transformer in an a.c. circuit? How do the input and output powers in a transformer compare?
Solution
A transformer is a device by which the amplitude of an alternating e.m.f. can be increased or decreased.
For an ideal transformer, when there is no loss of energy, the output power is equal to input power i.e.,
Power in secondary coil = power in primary coil
ESLS = EPLS
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