From Faraday’s law to the expanded Maxwell’s equations for a mechano-driven media system that moves with acceleration

Abstract

<p indent="0mm">In classical electrodynamics, by motion for either the observer or the media, it always naturally assumed that the relative moving velocity is a constant along a straight line (e.g., in an inertia reference frame), so that the electromagnetic behavior of charged particles in vacuum space can be easily described using special relativity. However, for engineering applications, the media have shapes and sizes and may move with acceleration, and recent experimental signs of progress in triboelectric nanogenerators have revealed pieces of evidence for expanding Maxwell’s equations to include media motion that could be time and even space dependent. Therefore, we have developed the expanded Maxwell’s equations for a mechano-driven media system (MEs-f-MDMS) by neglecting relativistic effect. This article first presents the updated progresses made in the field. Secondly, we extensively investigated Faraday’s law of electromagnetic induction for a media system that moves with an acceleration. We found that, the “anti-flux rule” examples outlined by Feynman in his book are just caused by the accelerated motion of the media, which were not included in Maxwell’s equations, but disregarded. This is a typical example that Maxwell’s equations have to be expanded for moving media. Therefore, the charged moving media are confirmed to be the sources of generating electromagnetic radiation (a motion-generated electromagnetic field); and the generated electromagnetic wave within the medium can be described using the expanded Maxwell’s equations. Most importantly, in comparison to the existing classical electrodynamics, the newly developed MEs-f-MDMS marks four unique advances, which have been summarized and the near field electrodynamics vs. the far field electrodynamics are proposed.