What about displacement current elements ?
Neither Ampère nor Weber speak of displacement currents.
Personally, I have no problem with displacement currents, which are very useful for understanding, nor with Maxwell's electromagnetism.
Let's remember what we are talking about. A study by Steffen Kühn, mentioned above by broli, claims to show a difference in experimental results, compared to the predictions either by Weber or by Maxwell.
I have pointed out an experimental bias, since Kühn does not take into account the electrostatic forces that will necessarily appear between the magnet and the two poles of the capacitor because the voltage is not negligible.
And I have shown with another, simpler setup, that the "current elements", taken alone, are not sufficient to describe the situation. Broli tells us that Weber's electrodynamics answers the problem, however, and from what I understand, it is because it also takes into account charges, not only currents, and therefore electrical forces, not only magnetic ones. I want to believe this, since Weber's electromagnetism is entirely based on the coulombic forces of moving charges. But this is not what is implemented in Kühn's text. He only deals with the question of current elements (his § 2.3), as if there were only magnetic forces, which is not true.
Finally, I have no more conceptual problem with Weber than with Maxwell, and even Weber is rather relevant. Because there is a third way to treat electromagnetism, and that is through relativity. Now in relativity, it is the Coulombian fields, deformed by the motion of the charges (because of the contraction of the lengths), which cause the magnetic effects. With relativity, as with Weber, the fundamental notion is the coulombic field. But again, Steffen Kühn's experiment cannot demonstrate what it claims because only magnetic forces are calculated, when electric forces will also be present.
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Topic: The interesting case of magnetic induction due to a Capacitor. (Read 19614 times)
