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Homework Help: Capacitor separated by a dielectric

  1. Oct 17, 2011 #1
    1. The problem statement, all variables and given/known data


    2. Relevant equations
    3. The attempt at a solution

    My discrepancy is with the last question labeled "Exercise" (What is the maximum energy that can be stored in the capacitor?).

    Since the max voltage is 16000V = 16000 J/C, why is multiplying the max voltage by the max charge (3.2 e-7 C) incorrect?

    Attached Files:

  2. jcsd
  3. Oct 17, 2011 #2
    The energy contained is U = 1/2*C*V^2
  4. Oct 17, 2011 #3


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    Staff: Mentor

    Because were you to start drawing off charge, the capacitor voltage would drop, so you don't have available that amount of charge at the max charged voltage.
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