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Homework Help: Finding the E in the mica

  1. Oct 11, 2005 #1
    A parallel-plate capacitor has a capacitance of 60 pF, a plate area of 130 cm2, and a mica dielectric ( = 5.4). At 60 V potential difference, calculate the following values.

    (a) E in the mica
    wrong check mark V/m

    (b) the magnitude of the free charge on the plates
    (c) the magnitude of the induced surface charge on the mica

    I tried the following:
    E = [Q/A]/(k*Eo);
    E = (1e-12/.013)/(5.4)(8.85e-12);
    E = 1.609 which is wrong.

    I got Q by the following: C = QV; Q = C/V; 60e-12/60 = 1e-12
  2. jcsd
  3. Oct 17, 2005 #2

    Tom Mattson

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    Sorry for the late reply. If you're still working on this then check out the websites I gave you in this thread and see if you don't have better luck.
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