A transformer has a core loss of 61 W and copper loss of 144 W. When it is carrying 20% over load current, the load at which this transformer will operates at the maximum efficiency

A transformer has a core loss of 61 W and copper loss of 144 W. When i

1.	A transformer has a core loss of 61 W and copper loss of 144 W. When it is carrying 20% over load current, the load at which this transformer will operates at the maximum efficiency
A.	80%
B.	66%
C.	120%
D.	44%
Answer» B. 66%

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A transformer has a core loss of 61 W and copper loss of 144 W. When it is carrying 20% over load current, the load at which this transformer will operates at the maximum efficiency

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