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Homework Help: Capacitors Charging Linearly

  1. Mar 16, 2010 #1
    1. The problem statement, all variables and given/known data
    When a does a capacitor increase in charge linearly?


    2. Relevant equations
    C=Q/V


    3. The attempt at a solution
    If I am correct, it is when the capacitor is being directly charged by a battery. When there is a resistor, we get an RC circuit scenario where capacitor charges exponentially.
     
  2. jcsd
  3. Mar 16, 2010 #2

    Jmf

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    Linearly with respect to what? time? Can V change too?

    If an ideal resistor were charged with an ideal (no internal resistance) battery, the plot of charge against time would not be linear but would look like a step, from what I understand.

    But of course in practice this is impossible, since there will always be some measure of resistance in the circuit. Does this help clear things up?

    Here's an interesting question: If V were to change over time, how would the plot of V against time look if the plot of Q against time was linear? (I think maybe this was what you were meant to work out).
     
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