Given the maximum efficiency of a transformer of a 500 kVA, 3300/500V, 50 Hz single-phase transformer is 97% and occurs at 3/4 of full-load, unity power factor. If the impedance is 10%, the regulation at full-load, power factor 0.8 lagging will be _____ % .

Given the maximum efficiency of a transformer of a 500 kVA, 3300/500V,

1.	Given the maximum efficiency of a transformer of a 500 kVA, 3300/500V, 50 Hz single-phase transformer is 97% and occurs at 3/4 of full-load, unity power factor. If the impedance is 10%, the regulation at full-load, power factor 0.8 lagging will be _____ % .
A.	8.25%
B.	17.52%
C.	7.52%
D.	10.52%
Answer» D. 10.52%

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Given the maximum efficiency of a transformer of a 500 kVA, 3300/500V, 50 Hz single-phase transformer is 97% and occurs at 3/4 of full-load, unity power factor. If the impedance is 10%, the regulation at full-load, power factor 0.8 lagging will be _____ % .

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