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Re: [Phys-l] Poynting Vector

As Curt suggests, this sounds like a static situation. If so, there is no EM wave, and, consequently, no Poynting vector.

On Sat, 28 Jun 2008, chuck britton wrote:

This is an excellent question.
Let's keep it simple - steady state no external circuits etc.

I'll suggest that we make it more real and less ideal using a simple
dipole to replace the capacitor.

Keep the positive point charge on the left etc.

Now look at the Poynting vector at locations other than directly
between the point charges.

Power is conserved

What is circulating besides electrical power??

Maybe the Vector Potential comes into play??

What about angular momentum?

On Jun 28, 2008, at Jun 28(Sat) 12:48 , Jeffrey Schnick wrote:

Consider a charged simple parallel plate capacitor in a static uniform
downward-directed magnetic field. The capacitor is oriented so that
from our point of view, the electric field between the plates of the
capacitor is directed rightward. Poynting tells us that between the
plates, energy is flowing away from us at a rate proportional to EB.
Where is that energy coming from and going to?
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