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A transformer of efficiency 90% draws an...

A transformer of efficiency 90% draws an imput power of 4kw. An electrical appliance connected across the secondary draws a current of 6A. The impedance of the device is

A

`60Omega`

B

`50Omega`

C

`80Omega`

D

`100Omega`

Text Solution

Verified by Experts

The correct Answer is:
D
`eta=P_(O)/P_(i)rArr` Output Power = `0.9xx4kW=3.6kW`
Now, `3.6kW=i^(2)RrArr36xxR=36xx10^(2)rArrR=100Omega`.
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