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Homework Help: Question on Circuits with Dielectric Problem

  1. Feb 9, 2008 #1
    Circuits with Dielectric Problem

    1. The problem statement, all variables and given/known data
    http://img412.imageshack.us/img412/2450/circuitgj6.jpg [Broken]
    The dielectric added has the value of 3.67.
    http://img504.imageshack.us/img504/5360/circuitquestionqw6.jpg [Broken]

    2. Relevant equations
    Series: 1/C=1/C1+1/C2...
    Parallel: C=C1+C2...

    3. The attempt at a solution
    So, I can find the normal voltage and charge with the dielectric in, but once the battery is removed, I am lost as to how everything balances out.

    Let the capacitors be numbered: 1 for the top left, 2 for the top right, and 3 for the bottom.
    Let Cxy be the total capacitance of x and y.
    C12 = 1/(1/3.48 + 1/(3.67*8.8))
    Removing the dielectric:
    C12' = 1/(1/3.48 + 1/8.8)
    Since V123 = V12, Q12 = C12' * V12

    But this is not correct. Any tips on how everything balances out when you remove the dielectric?

    Last edited by a moderator: May 3, 2017
  2. jcsd
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