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How much current is drawn by the primary...

How much current is drawn by the primary coil of a transformer which steps down 220 V to 22 V to operate device with an impedance of 220 ohm.

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Given `epsilon_(1) = 220 V , epsilon_(2) =22V `
`I_(1)= 6 A, I_(2) = 50 A `
Input power `= epsilon_(1)I_(1)=22xx50=1100 W `
Efficiency of transformer is
`n = ("Output power") /("Input power")xx100 `
`=(1100)/(1320)xx100 % = 83.3 % `
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