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In a series RLC AC circuit (ideal ammeter and voltmeter), the resistance R = 3 ohm, inductive reactance X_L = 7 ohm, and capacitive reactance X_C = 3 ohm. Which of the following statements is correct?

Reading of V2 is 60*sqrt(2) volt
Reading of V1 is 40*sqrt(29) volt
Reading of V1 is 40 volt
Impedance of circuit is 5 ohm and power factor is 3/5

Correct answer: Impedance of circuit is 5 ohm and power factor is 3/5

Solution

Net reactance = 7 - 3 = 4 ohm. Impedance Z = sqrt(3² + 4²) = sqrt(25) = 5 ohm. Power factor = R/Z = 3/5.

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