A transformer is used to light a 140 W, 24 V bulb from a 240 V AC mains. The current in the main cable is 0.7 A. find the efficiency of the transformer.

A transformer is used to light a 140 W, 24 V bulb from a 240 V AC main

1.	A transformer is used to light a 140 W, 24 V bulb from a 240 V AC mains. The current in the main cable is 0.7 A. find the efficiency of the transformer.
Answer» Solution :Efficiency `=("Output POWER")/("INPUT power")xx100` `eta=(140)/(240xx0.7)xx100=83.3 %`

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A transformer is used to light a 140 W, 24 V bulb from a 240 V AC mains. The current in the main cable is 0.7 A. find the efficiency of the transformer.

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