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Question
The potential difference across the resistor is 160V and that across the inductor is 120V. Find the effective value of the applied voltage. If the effective current in the circuit be 1.0 A, calculate the total impedance of the circuit.
Solution
eL = 120 V eL = i × L
eR = 160V eR = iR
`R = e/i = 160/1 = 160 Ω `
`X_L = 120/1 = 120 Ω `
`Z = sqrt(R^2 + X_L^2 `
` = sqrt ((160)^2 + (120)^2)`
` = sqrt( 25600 + 14400)`
` = sqrt(40000)`
`Z = sqrt( 4 xx 1.4 ) = 200 Omega`
Z = 200 Ω
effecience voltage
e = iZ
e = i × 200 = 200V
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