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icyspicy
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Homework Statement
If the rms voltage across the generator is 149 V, calculate the average power P(at 402 Hz) being used by the circuit.
R = 298 Ω, a capacitance C = 4.1 μF, inductance of L = 0.23 H
https://tycho-s.physics.wisc.edu/cgi/courses/shell/common/showme.pl?courses/phys104/spring09/homework/07/rclseries/ex2s92p4.gif
Homework Equations
V=IR
Avg power=Vrms*Irms(cos phase angle)
vrms=vmax/(sqrt 2)
Irms=Imax/(sqrt 2)
The Attempt at a Solution
Vrms=IrmsR
149/(sqrt 2)=Irms*298 I think that the 149 V given in the problem needs to be divided by 2 to get Vrms? is rms voltage across generator same as max voltage? I'm not exactly sure about that part...anyways I got:
Irms=.35355
Avg power= (.35355)(149/sqrt 2) cos (phase angle)
i solved for XL (581) and XC (96.6), which were both correct. so I got the phase angle to be 58.4 degrees
Avg power= (.35355)(149/sqrt 2) cos (58.4)
I'm not getting the right answer, so maybe my approach was wrong? Any help is appreciated.
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