Capacitor Problem: Charge, Electric Displacement, and Current Calculations

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Homework Statement


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.


Homework Equations


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

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?
 
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Rewrite that with \LaTeX code,I think it`s easy as it can be.

It`s pain to read like that.
 
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