Question

Power in an AC Circuit

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E," sin(wt) n Sin(a) t a C L C R b 110000 d

A circuit is constructed with an AC generator, a resistor, capacitor and inductor as shown. The generator voltage varies in time as ε =V_a - V_b = ε_msinωt, where ε_m = 120 V and ω = 314 radians/second. The inductance L = 283 mH. The values for the capacitance C and the resistance R are unkown. What is known is that the current in the circuit leads the voltage across the generator by φ = 44 degrees and the average power delivered to the circuit by the generator is P_avg = 76 W.

1)

What is I_max, the amplitude of the current oscillations in the circuit?

A

2)

What is R, the value of the resistance of the circuit?

Ω

3)

What is C, the value of the capacitance of the circuit?

μF

4)

The value of ω is now changed, keeping all other circuit parameters constant, until resonance is reached. How was ω changed?

ω was decreased

ω was increased

5)

What is the average power delivered to the circuit when it is in resonance?

W

Answer 1

1-76 2-44

tey 4.1 1469