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Homework Help: RC circuit problem

  1. Feb 25, 2007 #1
    1. The problem statement, all variables and given/known data

    In Figure P18.50, suppose that the switch has been closed for a length of time sufficiently long enough for the capacitor to become fully charged. (R = 12.0 k, R2 = 17.0 k, R3 = 1.00 k, V = 9.70 V)

    The picture is under attachment

    a) Find the steady-state current in each resistor.
    I1 = µA?
    I2 = µA?
    I3 = µA ?

    (b) Find the charge on the capacitor.
    µC ?

    2. Relevant equations

    R = V / I

    q = Q e^(-t/RC)

    3. The attempt at a solution

    Well, since after the switch is closed, I figured all 9.7 V goes to the first resistor, so I used R = V / I to get the current for the first one. But it's wrong.

    Attached Files:

  2. jcsd
  3. Feb 26, 2007 #2


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    Staff: Mentor

    It's wrong because there is a voltage divider formed with one of the other two resistors in the steady state. Which one? In the steady state, what is the voltage across the capacitor?
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