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

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

1.	A transformer has an efficiency of 80%. It works at 100V and 4kW. If secondary voltage is 240 V, the current in primary coil is ……
Answer» 0.4 A `4 A` `10 A` `40 A` Solution :Power of 100 V and I ampere for transformer is`4xx10^3` W `therefore 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 100V and 4kW. If secondary voltage is 240 V, the current in primary coil is ……

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