(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Show that the displacement current density which flows when a parallel plate capacitor gets charged is ε(dE/dt) where ε is the permittivity of the medium between the capacitor. What is the energy density stored in the capacitor and the force per unit area (pressure) on the plates?

2. Relevant equations

D=ε_{o}E + p= ε_{o}E +ε_{o}χE=εE

p=[itex]\alpha[/itex]E (mircoscopic)

p=χE (marcoscopic)

(Constitute of Relations) p is the polarization of the medium

3. The attempt at a solution

(a) I am really confused as to how to show the first part, which I think is needed for the whole problem.

(b) For the work, from my notes I have[itex]\tau\tau[/itex]=[itex]\sigma[/itex]E which means it behaves equivallently to Ohms Law V=IR so the Voltage which is the work done per unit charge is equal to that expression.

(c) For the energy density of the capacitor U_{e}=1/2 ε_{o}E^2

And the Total energy density is U_{t}=ε_{o}/2 *E^2 +B^2/2μ_{o}which reduced to 2ε_{o}E^2

(d) P=1/2 ε_{o}E^2 +B^2/μ

P=ε_{o}E^2

P=s/c (s is the Poynting vector)

I am just really confused but this is what my notes and external sites have led me to. Any help to make sense of this is appreciated (I'll be talking to my professor today too as well so hopefully I can understand this better)

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