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A transformer is employed to reduce 220V...

A transformer is employed to reduce `220V` to `11V`. The primary draws a current of `5A` and the secondary `90A`. The efficiency of the transformer is

A

`20%`

B

`40%`

C

`70%`

D

`90%`

Text Solution

Verified by Experts

The correct Answer is:
D
`eta=(V_(s)i_(s))/(V_(p)i_(p))xx100=(11xx90)/(220xx5)xx100=90%`
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