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RC Circuit and finding Maximum Voltage

  1. Feb 23, 2009 #1
    1. The problem statement, all variables and given/known data

    Use the value:
    E = 200 V,
    Horizontal resistor R1 = 1136 capital omega,
    Vertical resistor R2 = 568 capital omega, and
    Capacitor C = 5.37 mu or micro F,


    (a) the initial current through the battery just after the switch is closed:
    (b) the steady state current through the battery when the switch has been closed for a long time:
    (c) the maximum voltage across the capacitor:

    2. Relevant equations

    R = V/I
    C = Q/V

    3. The attempt at a solution

    I found a and b to be as follows (using loops)

    a) 0.176056 A
    b) 0.117371 A

    I'm having trouble with part c)....I don't know how to relate the current i found in part a) or b) to the definition of capacitance to find the maximum voltage. Could anyone help or point me in the right direction? thanks!
  2. jcsd
  3. Feb 23, 2009 #2


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    Homework Helper

    Your a and b look good to me. The capacitor will be charged so the voltage across it is equal to the voltage across R2. No current will flow through the capacitor (it blocks DC), so the voltage on R2 is the same as if their was no capacitor there.
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