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Gary,
There is not the slightest bit of mystery in the "conservation of electron flow". An important relationship in electromagnetics is the so-called continuity equation. In simple terms this is an expansion of Kirchhoff's current law. It says that any current imbalance at a point in space must be compensated by a change in the stored charge at that point in space. You can see the exact equation in any mid-level text on E&M. This is how capacitors work. Current flows in but does not pass through the gap between the plates. Instead, charge is stored on the plates. It is sometimes convenient to describe this behavior in terms of displacement current through the gap, but of course no electrons actually pass between the capacitor plates. Antennas work the same way. Any change in current along the antenna must be accompanied by a change in stored charge. The antenna acts as a capacitor. Everyone talks about high voltage at the tips of a dipole antenna, but perhaps fewer people understand there is a buildup of stored charge as well. 73, Gene W4SZ JGBOYLES wrote: "If you look at HOW an inductor works, the current flowing in one terminal ALWAYS equals the current flowing out the other terminal." I think that is true. If you define current as electron flow, then the fields and radiation that a large coil may be subjected to, will not increase or decrease the number of electrons that the coil contains. As such, the amount of electrons entering the base of the coil, will equal the same number exiting the coil, with time displacement. Consider a large physically long capcitor, with multiple plates. One can use this as a loading element. There is no electron flow between plates. However there is "displacement" current between the plates that has no physical meaning. Now what? The capacitor will be just affected as a coil. So, from the conservation of electron flow I don't know what to believe. 73 Gary N4AST |
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