The system is a parallel plate capacitor, top plate has charge density sigma, bottom play has charge density -sigma. I'm looking for the "field momentum" inside the cubic volume Omega shown in the picture.(adsbygoogle = window.adsbygoogle || []).push({});

My book (Griffiths) is a little unclear on exactly what this is, and seems to be saying that the momentum is proportional to the Poynting vector ExB, so since there doesn't seem to be a magnetic field, this would suggest the field momentum is zero.

Is this correct?

The only problem I'm having is that, later in the problem, it asks if there's a net flow of field momentum into the cube, so I'm thinking there's more to the problem than what I'm seeing. Could anyone help clear this up?

Thanks.

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# Field momentum inside a parallel plate capacitor

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