Question

a transformer is used to light 140watt 24V lamp fr5om 240 V ac main cable is 0.7amp.the effciency of ntransformer isy

Answer 1

Answer:

83.3%

Mains voltage is 240V and mains current is 0.7amp so inpur power will be 240×0.7=168watt

But output power is given as 140 Watt so efficinecy=(output/input)×100 % =83.33 %

Explanation:

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