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There are many examples of electronic magnetic levitation devices. These generate variable strength magnetic fields to keep an object levitated above a base. For example https://www.youtube.com/results?search_query=magnetic+levitation .

Now as I understand it magnetism follows an inverse cube law as opposed to an inverse square law for the force between two charges.

So I wonder if in theory you could lift more weight using less energy if you used that instead of a generated magnetic field. I have only seen very simple examples of electrostatic levitation. Is it possible to make it scale up?

For example, could you take a metal ball or better a pin on which you generate a massive charge (via a mechanism inside) but cover it with an insulator so that the charge cannot dissipate and use the force between several such devices (varied dynamically by a control mechanism) to make a 'static' levitator that lifts a decent sized weight but uses less energy to do so?

By less energy I mean that we exploit the square law vs cube law improvement to lift more weight with proportionally less input energy. The same lifting force is required to counter gravity but I'm not sure where energy is being expended here. The current used to drive the electromagnets is the main cost for the first case. Some kind of 'charge pump' for the second I guess.

The charges would be varied dynamically to stabilize the system. So I guess this would be dynamic electrostatic leviation (electrodynamic has other implications).

I think the reason this would not work is the force and insulation requirements are conflicting. If the insulator is good then presumably it disupts the force between the charged objects it is separating. If you leave a gap then the force is limited by when the charge becomes large enough to generate a spark. Is this reasoning sound?

Or are there any larger scale examples out there?

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