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Homework Help: Capacitor help please

  1. Feb 9, 2007 #1
    capacitor help please!!!!!

    I had a lab where we had a circuit with a capacitor and we measured the charging time of the capacitor. We then added a capacitor in series and measured the charging time and then added one in parallel and measured the charging time. The question asks how the addition of the new capacitor affects the charging time of the capacitor.... from our calculations (which may or may not be right...) I've determined that "when a capacitor is added in series the charging time is decreased and when it's added in parallel the charging time is increased"... can anyone give me any input on whether or not that statement is true. thanks
  2. jcsd
  3. Feb 9, 2007 #2


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    Gold Member

    Have you taken a look at the time constant equation: T=RC? In your circuit only the value of C is changing as you place capacitors in series and parallel. Assuming that you know to find the total capacitance in series or parallel, you can reassure yourself as to whether your conclusion was correct.
    Last edited: Feb 9, 2007
  4. Feb 9, 2007 #3


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    Yes, your experiment gave valid results.

    Two capacitors in parallel basically create a larger capacitor. If you added the capacitances together and plugged that into the equation ranger mentioned, your calculated time should come somewhat close to your measured time (your tolerances for capacitors is about 10% and tolerances for resistors are about 5%, so I'd be surprised if your time wound up right on).
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