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A transformer has an efficiency of 80%. ...

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

0.4 A

B

`4 A`

C

`10 A`

D

`40 A`

Text Solution

Verified by Experts

The correct Answer is:
D
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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