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Homework Help: Problem on capacitors.

  1. May 5, 2008 #1
    1. The problem statement, all variables and given/known data
    Given an electric potential of Vo*sin(wt). This is applied to a parallel plate capacitor of area S, separation d and capacitance C. The questions are
    a) What is charge Q on the plates?
    b) Find the electric displacement current
    c) Calculate the current in the wire.

    2. Relevant equations
    a) Q=CV
    b) I=(epsilon)*d(phi)/dt
    c) i=dQ/dt

    3. The attempt at a solution

    for part a, i got Q=CV=C*Vo*sin(wt)
    for part b, i got I=(epsilon)*w*cos(wt)
    for part c, i got i=C*w*cos(wt)

    is this right, because i have a feeling that this is a little too easy of an answer.
    why does the displacement current differ from the current in the wire?
  2. jcsd
  3. May 5, 2008 #2
    Rewrite that with [tex]\LaTeX[/tex] code,I think it`s easy as it can be.

    It`s pain to read like that.
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