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A transformer is used to light a 100 W a...

A transformer is used to light a `100 W` and `110 V` lamp from a `220V` mains. If the main current is `0.5 A`, the Efficiency of the transformer is approximately:

A

`10%`

B

`30%`

C

`50%`

D

`90%`

Text Solution

Verified by Experts

The correct Answer is:
d
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