I would like to compile a short list of inverse-exponent force magnitude fall-off laws for several simple geometries for material made of monopoles and for material made of parallel dipoles (of negligible length).(adsbygoogle = window.adsbygoogle || []).push({});

Far fieldforcefor any two objects is, of course, proportional to [itex]1/r^2[/itex] for monopole-based objects, and [itex]1/r^4[/itex] for dipole-based objects (yes, field for dipoles drops with [itex]1/r^3[/itex], but i'm interested in force between two objects that are both made of dipoles. The definition for field strength is related to the force on a monopole).

So what is the force magnitude fall-off (both monopole and dipole material) for the following near-field geometries?:

a point near a line

a line near a parallel line

a line near a perpendicular line

(Side note: the field above a plane made of dipoles is uniform, so there will be zero force (except torque) on dipoles above it)

Thanks.

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# Inverse square & cube laws for various geometries

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