If a transformer is fed from a dc rather than a 1-phase ac supply, then the transformer will __________(a) burn its windings(b) operate normal(c) will not operate(d) will give very small leakage fluxThe question was posed to me in a national level competition.I'm obligated to ask this question of Equivalent Circuit of Transformer topic in portion Transformers of Electrical Machines

If a transformer is fed from a dc rather than a 1-phase ac supply, the

1.	If a transformer is fed from a dc rather than a 1-phase ac supply, then the transformer will __________(a) burn its windings(b) operate normal(c) will not operate(d) will give very small leakage fluxThe question was posed to me in a national level competition.I'm obligated to ask this question of Equivalent Circuit of Transformer topic in portion Transformers of Electrical Machines
Answer» Right choice is (a) BURN its windings To elaborate: Dc is nothing but AC at ZERO FREQUENCY. So the reactance will be zero and the current will be limited solely by the small resistance of the winding which will produce very high amount of current to flow through the windings, so burning them up.

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