No load current in a transformer: (A) lags the applied voltage by 90° (B) lags the applied voltage by somewhat less than 90° (C) leads the applied voltage by 90° (D) leads the applied voltage by somewhat less than 90°

No load current in a transformer:
 (A) lags the applied voltage by 90°
(B) lags the applied voltage by somewhat less than 90°
 (C) leads the applied voltage by 90°
 (D) leads the applied voltage by somewhat less than 90°
by

1 Answer

Answer :

Ans: B
The primary input current under no load conditions has to supply (i) iron losses in
the core i.e hysteresis loss and eddy current loss (ii) a very small amount of Cu loss
in the primary (there being no Cu loss in secondary as it is open)
by

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