A transformer has an efficiency of 80%. It works at 100 V and 4kW. If secondary voltage is 240 V, the current in primary coil is ……..

A transformer has an efficiency of 80%. It works at 100 V and 4kW. If

1.	A transformer has an efficiency of 80%. It works at 100 V and 4kW. If secondary voltage is 240 V, the current in primary coil is ……..
Answer» `10 A` `4 A` `0.4 A` `40 A` SOLUTION :`P_1=V_1 I_1` `THEREFORE I_1=P_1/V_1` `=(4xx10^3)/100=40` A

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A transformer has an efficiency of 80%. It works at 100 V and 4kW. If secondary voltage is 240 V, the current in primary coil is ……..

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