# "Bouncing" on a dielectric?

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Ok so I have been reviewing some old basic electricity and magnetism material (Gauss’ Law, Maxwell’s Equations etc.) in preparation of the new school year and I came up with what I think is an interesting although most likely not feasible idea, and I wondered what other people thought about it.

Basically the idea is to “bounce” on top of a dielectric using an electric field. Imagine we have a metallic object situated above a flat plane made out of some dielectric material. Also imagine that we have the ability to turn on and off an extremely large electric charge on this metal objects surface, at a rate many many times the relaxation time of the dielectric material beneath the metallic object. I think in theory it should be possible to use this alternating charge on our object (+Q, and 0) to “bounce” on top of the dielectric. The process would occur like this:

Time0 -> Q=0, dielectric has no net polarization.

Time1 -> Q=+Q, dielectric begins to polarize (we reach our maximum Q an order of magnitude faster than the dielectric can polarize)

Time2-> Q=+Q, dielectric has become fully polarized due to the gigantic charge located above it

Time3-> Q=0, dielectric is still very polarized but begins to relax (we can decrease Q to zero an order of magnitude faster than the dielectric can polarize)

Time4-> Q=0, dielectric has no net polarization.

Process repeats.

Now over the exceedingly small but finite time that the positive and negative ends of the dielectric swap places if we are able to flip our charge Q counterpoint to the polarization of the dielectric, the charges in the dielectric should repel Q. This reverse force would exist only for an extremely small instant as the dielectric begins to polarize and impart only a tiny tiny amount of impulse per displaced charge. However the relaxation time of some materials is extremely fast, and we could potentially obtain millions if not billions of “bounces” per second off of many moles worth of dielectric molecules. A few initial bounces would be “lost”, due to setting up the timing, very much like what happens in an induction motor as it starts.

This is of course assuming that we could turn on and off our gigantic Q that quickly. There are many many practical reasons why this would not actually be feasible, another one would be that Q would probably have to be on an order of magnitude that would most likely end up creating lightning anyways. I cannot however think of any theoretical ones why it wouldn’t work. What do you think?

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