1) If a simple parallel plate capacitor connected to a circuit, and discharging, were to move in an exterior magnetic field, what would happen to the interior region?

Interior region components:

  • Positive & Negative plates.
  • Dielectric material.
  • No dielectric material(vacuum)

2) That same moving capacitor (while discharging) is exposed to a time-varying magnetic field. What effects could occur?

Ideas that come to mind:

  1. Eddy currents
  2. Time-varying induced electric field
  3. Lorentz force(Highly doubt it can contribute anything, in the case of vacuum gap between the plates it does not interact with displacement currents, in the case of a dielectric material the polarization would not yield to a net-positive force in any direction... they should cancel out).
  • \$\begingroup\$ What mutual inductance is there? How will the magnetic field influence a capacitor rotating or not. At low f nada. Only the conductors with inductance can induce a voltage from the B field. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 May 5 '19 at 18:24
  • \$\begingroup\$ But the inductance of free space is small so the coupling will also be small but rotating the conductors does not affect the inductance so the rotation has no effect expected. Until you get to the 1/4 wavelength frequency of the path between the capacitor. Then any wobble will or modulation of capacitance will cause noise if erratic or if the gave is small enough to cause arcing. I discovered this using 928MHz Tx on a power meter with a rotating disc on an magnetic air bearing . \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 May 5 '19 at 18:30
  • \$\begingroup\$ It was only old power meters with Devron plastic bearings outside the magnetic air bearing that caused static discharge and poor RF reception when the disc rotated. Circa mid 90’s Iris Systems Inc 2 way AMR. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 May 5 '19 at 18:35
  • \$\begingroup\$ @SunnyskyguyEE75 I haven't considered rotation, what I imagined relative to the problem would be translational. Regarding the mutual inductance, it's mostly the connection wires and leads, however, the inductance of the "capacitor" itself is unknown. Can electromagnetic induction occur within the interior of the capacitor? While moving perpendicular to the exterior magnetic field, in addition, can Lorentz force occur? \$\endgroup\$ – e.d.m - II May 5 '19 at 19:12

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