A single - phase 50 kVA, 250V/ 500 V two winding transformer has an efficiency of 95% at full load, unity power factor. If it is reconfigured as a 500 V/ 750 V auto-transformer, its efficiency at its new rated load at unity power factor will be

A single - phase 50 kVA, 250V/ 500 V two winding transformer has an

1.	A single - phase 50 kVA, 250V/ 500 V two winding transformer has an efficiency of 95% at full load, unity power factor. If it is reconfigured as a 500 V/ 750 V auto-transformer, its efficiency at its new rated load at unity power factor will be
A.	95.752%
B.	97.851%
C.	98.276%
D.	99.241%
Answer» D. 99.241%

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A single - phase 50 kVA, 250V/ 500 V two winding transformer has an efficiency of 95% at full load, unity power factor. If it is reconfigured as a 500 V/ 750 V auto-transformer, its efficiency at its new rated load at unity power factor will be

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