Is the electrostatic force between a point charge and a neutral metallic object always attractive?

Michael Levin; Steven G. Johnson

doi:10.1119/1.3595554

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arXiv · 1007.2175

Is the electrostatic force between a point charge and a neutral metallic object always attractive?

Michael Levin·Steven G. Johnson

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Abstract

We give an example of a geometry in which the electrostatic force between a point charge and a neutral metallic object is repulsive. The example consists of a point charge centered above a thin metallic hemisphere, positioned concave up. We show that this geometry has a repulsive regime using both a simple analytical argument and an exact calculation for an analogous two-dimensional geometry. Analogues of this geometry-induced repulsion can appear in many other contexts, including Casimir systems.

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Michael Levin, Steven G. Johnson. 2010-07-13. Is the electrostatic force between a point charge and a neutral metallic object always attractive?. https://doi.org/10.1119/1.3595554

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