What is the efficiency of an auto-transformer in comparison to that of a two-winding transformer of the same rating?

What is the efficiency of an auto-transformer in comparison to that of a two-winding transformer of the same rating?

A. Slightly less than that of a two-winding transformer,
B. Same as that of a two-winding transformer.
C. More than that of a two-winding transformer.
D. As low as 1/5th of the efficiency nf a two-winding transformer.

Show Answer

Answer: C

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