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Homework Help: Help capacitance of two different capacitors!

  1. Oct 6, 2005 #1
    Two capacitors are identical, except that one is empty and the other is filled with a dielectric ( = 4.30). The empty capacitor is connected to a 21.0 V battery. What must be the potential difference across the plates of the capacitor filled with a dielectric such that it stores the same amount of electrical energy as the empty capacitor?

    so here's my problem..... i don't have the distance across the plates or the plate area??? would i just start going into the equations and seeing if i can cancel things out???

    any help would be appreciated
  2. jcsd
  3. Oct 6, 2005 #2

    Tom Mattson

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    kpangrace, please do not multiple threads for the same topic. It makes discussions impossible to follow. Also, Moderators here will automatically delete duplicate threads, and one of them zapped the version that I already responded to. Now I have to respond again. :grumpy:

    Yes, do that. You will find that you can cancel things out on the basis that the two capacitors are identical (except of course for the dielectric).
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