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Homework Help: RLC circuit in series

  1. Sep 28, 2010 #1
    1. The problem statement, all variables and given/known data
    A series RLC circuit consists of a 100 ohm resistor, a 0.10 H inductor, and a 100 micro farad capacitor. It is attached to a 120 V/60 Hz power line. What is the peak current, I?


    2. Relevant equations
    I=V/Z
    Z=sqrt(R^2+(omegaL - (omegaC)^-1))
    omega=2pif


    3. The attempt at a solution
    I=120/sqrt(100^2+(2pi(60)*.1 - (2pi(60)*100x10^-6)^-1)^2)=1.2
    The program is saying it's wrong.
    I'm confused what I'm doing wrong, exactly. I'm thinking the omega is wrong, but I don't know how I would get omega otherwise.
    Thanks for your help.
     
  2. jcsd
  3. Sep 28, 2010 #2
    I eventually figured it out... apparently 120 V is the rms value, which they clearly do NOT indicate what-so-ever... so my value of I was really I rms, and they just wanted it in I. My answer times sqrt(2) gave me the correct answer.
     
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