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RC circuit question

  1. Dec 8, 2008 #1
    Why is time in a series RC circuit linearly dependent on capacitance as charging/discharging time is increased? (same with resistance) I thought RC circuits were exponential.
    Last edited: Dec 8, 2008
  2. jcsd
  3. Dec 8, 2008 #2


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    Please don't think I'm being rude. I'm just picky. I want to be helpful, but I'm getting sleepy, so this will be terse.

    I can only assume that you mean "time constant" for the first "time" in this sentence. This is just a consequence of the very simple definition.

    This doesn't mean anything. Perhaps you mean that the dependence of the value of some electrical property depends exponentially on time?
  4. Dec 8, 2008 #3


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    Or to put it another way:

    The voltage and current are exponential functions of time.

    The time required for the voltage or current to reach a specific value is proportional to RC. For example, the time in which the capacitor voltage reaches 50% of its final value.
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