Engineering Calculating the effective value and frequency of AC Circuit

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The discussion centers on calculating parameters for an AC circuit with given values for capacitance, inductance, and impedance. The user initially miscalculated the angular frequency (w) due to confusion about the direction of current and voltage. After realizing that the reactance value was incorrectly labeled, they corrected it to proceed with the calculations. The user concluded that a complex analysis was necessary to accurately solve for the effective values of current and voltage. The thread highlights the importance of correctly identifying circuit components and their roles in AC analysis.
diredragon
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Homework Statement


For AC Circuit shown in the picture, ##C=60nF##, ##L=100uH##, ##X_3=-100Ω##, ##Z_2=50Ω## and ##Φ_2=\frac {\pi}{6}##. When the switch is closed the ammeter shows a current ##I_1=0.6A## and the voltmeter shows ##U_l=60V##. The measuring instruments mentioned are ideal. Calculate:
a) ##w##
b) effective value of ##E##
c) ammeter result ##I'_1## when the switch is open.
The Circuit:
circuit.png


Homework Equations


3. The Attempt at a Solution [/B]
The first thing i noticed is that the direction of current and voltage isn't given so I need to guess it. I started from the ammeter and guessed that the flow of current is downwards.
From there, ##U_1 = I_1*X1## = -60V## with a + sign at the top node. Once i have this voltage i can find the current ##I_2 = \frac {U_1}{Z_2} = -1.2A##. With the two currents meeting at the top node, the current ##I_l = I_c## of the top node equals ##I_l=0.6A##.
circuit.png

Since i have ##U_l = I_l*wL##, ##w = \frac{U_L}{I_lL} = 10^6## which is not the correct answer.
The answer should be ##w = \frac {\sqrt 3}{3}10^6##. I can't go on solving the other parts if the first is not correct. What did i do wrong?
 

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There are no DC voltages or amperage's in this circuit. Everything is AC.
The 60V and 600mA are presumably rms.

Also, I do not know what your "X3=−100Ω" refers to.
Unless that is the value for X1 (using a capacitor symbol).

If X1 is not a cap, then part of the circuit have a DC component to the current, but still not the volt meter.
 
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.Scott said:
There are no DC voltages or amperage's in this circuit. Everything is AC.
The 60V and 600mA are presumably rms.

Also, I do not know what your "X3=−100Ω" refers to.
Unless that is the value for X1 (using a capacitor symbol).

If X1 is not a cap, then part of the circuit have a DC component to the current, but still not the volt meter.
The ##X_3## was supposed to be ##X_1##. I solved it now, i thought i could work with effective values of currents only but i guess i needed a complex analysis to solve it.
 

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