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Finding the Charge on a Capacitor

  1. Sep 25, 2011 #1
    I was given this problem throught WebAssign for my physics class:
    I am given an image of a power supply, followed by a circuit, a resistor1, then it breaks in two paths, one leading to another resistor2 and the other leading to a capacitor and then another resistor3, then the two paths come together and meet back at the power supply.
    For each of these I am given the values:
    R1=13000 [itex]\Omega[/itex]
    R2=18000 [itex]\Omega[/itex]
    R3=2000 [itex]\Omega[/itex]
    dV=8.1 V
    Capacitor=1.0E-5 F

    The first part of the question asked for me to find the current in each of the resistors, which was fairly simple.
    To do this, I used the formula:
    to get 261 [itex]\mu[/itex]A for the first and second resistors, and 0 for the thirds, as when the switch was thrown, the capacitor had to charge and no current reached that resistor.
    Now, I am completely lost as to how to find the charge on the capacitor. I have searched for methods, and have only managed to confuse myself even more. I do not know what formula to use. If I did, this would be much, much easier. Can anyone help me?
    Attached is a file containing the exact problem copied to microsoft word. Any assistance you can offer will be greatly appreciated!
  2. jcsd
  3. Sep 25, 2011 #2
    The attachment didn't go through! I'm sorry guys, I'm not sure what happened. :(
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