Average Power Calculation in RLC Circuit at 402 Hz?

AI Thread Summary
To calculate the average power in an RLC circuit at 402 Hz with an rms voltage of 149 V, the resistance is 298 Ω, capacitance is 4.1 μF, and inductance is 0.23 H. The equations for average power and rms values are utilized, with the user initially confused about the relationship between rms and maximum voltage. After calculating the inductive and capacitive reactances, the phase angle was determined to be 58.4 degrees. The user ultimately resolved their confusion and found the correct average power value. The discussion emphasizes the importance of understanding rms voltage in power calculations.
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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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nevermind, got it
 

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