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A step-down transformer is used on a 100...

A step-down transformer is used on a `1000 V` line to deliver `20A` at `120V` at the secondary coil. If the efficiency of the transformer is `80%` the current drawn from the line is.

A

0.125

B

30 A

C

0.3 A

D

2.4 A

Text Solution

Verified by Experts

The correct Answer is:
A
`eta=P_(O)/P_(i)rArr0.8=(V_(S)I_(S))/(V_(P)I_(P))rArr0.8=(120xx20)/(1000xxi_(p))rArri_(p)=3A`
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