The discussion revolves around the behavior of surface charge in capacitors, particularly focusing on the effects of DC and AC potentials, the skin effect, and how physical changes to the capacitor's structure might influence charge distribution and electric field penetration. The scope includes theoretical considerations and conceptual clarifications related to electromagnetism and capacitor dynamics.
Participants express differing views on the relationship between AC and DC potentials and their effects on surface charge depth, as well as the impact of physical changes to the capacitor. The discussion remains unresolved with multiple competing perspectives on these topics.
Participants note that the depth of electron displacement is contingent on various factors, including voltage and capacitance, and that changes in geometry or material properties can influence charge distribution without necessarily affecting deeper penetration of electric fields.
Well , is the surface current that you talk about parallel to the plate surface or perpendicular? Because @Ivan Nikiforov claims and shows even with an animation that there is only perpendicular movement of electrons due to the change in plate location. You left out that distinction but that is an important one, which causes some misunderstanding to me.Baluncore said:A small positive patch, close to a large negative plate, will draw electrons out of the large plate surface. Since C = Q / V, the charge drawn out will be Q = C⋅V ; That is, for a fixed voltage, charge is proportional to the capacitance.
If the positive patch is then moved around on the plate, the mound of electrons on the plate surface will be dragged about, following the moving patch. A momentary surface current of electrons will flow, where the edge of the small moving patch, covers or uncovers the larger plate.