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Homework Help: Discharge of capacitor

  1. May 4, 2010 #1
    1. The problem statement, all variables and given/known data
    When a condenser discharges electricity, the instantaneous rate of change of the voltage is proportional to the voltage in the condenser.
    Suppose you have a discharging condenser and the instantaneous rate of change of the voltage is 1/100 of the voltage (in volts per second). How many seconds does it take for the voltage to decrease by 90%?


    2. Relevant equations

    e^-rt

    3. The attempt at a solution Log 90= e^-t ? = 4.49?
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. May 4, 2010 #2
    It's wrong. Try to give a more detailed calculation and explain what it is you do.
     
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