Calculating the effective value and frequency of AC Circuit

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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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on Phys.org
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.