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A transformer is used to reduce the main...

A transformer is used to reduce the main supply of 220V to 22V. If the currents in the primary and secondary are 2A and 15 A respectively, then the efficiency of the transformer is

A

0.65

B

0.75

C

0.8

D

0.9

Text Solution

Verified by Experts

The correct Answer is:
B
`eta = (V_(S)I_(S))/(V_(P)I_(P)) xx 100 = 22/220 xx 15/2 xx 100 = 75%`.
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