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Homework Help: Alternating current circuits

  1. Mar 1, 2008 #1
    1. The problem statement, all variables and given/known data
    A light bulb has a resistance of 212 . It is connected to a standard wall socket (120 V, 60.0 Hz). (a) Determine the current in the bulb. (b) Determine the current in the bulb after a 13.2-μF capacitor is added in series in the circuit.

    2. Relevant equations
    R, V, f are given. I don't know how to start incorporate these figures without a value for Z. Am I forgetting a another important equation?


    3. The attempt at a solution
    I used the equations:
    X(sub L)=2pifL
    Irms=Vrms/Z
     
  2. jcsd
  3. Mar 1, 2008 #2

    cepheid

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    Gold Member

    Why??? There is no inductor in the circuit!
    Okay, good. Z is the impedance. What is the impedance of the circuit with just the resistor? What about after adding a capacitor?
     
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