The hysteresis and eddy current losses of a single phase transformer working on 200 V, 50 Hz

The hysteresis and eddy current losses of a single phase transformer working on 200 V, 50 Hz supply are Ph and Pe respectively. The percentage decrease in these when operated on a 160 V, 40 Hz supply are 

 (a) 32, 36 (b) 20, 36 (c) 25, 50 (d) 40, 80 
by

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Answer :

The hysteresis and eddy current losses of a single phase transformer working on 200 V, 50 Hz supply are Ph and Pe respectively. The percentage decrease in these when operated on a 160 V, 40 Hz supply are 20, 36

by

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