I Capacitor surface charge movement current, relativistic effects

[FusionJim]

This is the description of the thought experiment. There are two plates forming a parallel plate capacitor. Both plates are rectangular but one is large and long and the other is much smaller. Both are "charged up", the difference is that the smaller plate has surface charge across it's full surface area, meanwhile the larger plate only has surface charge within an area directly underneath the smaller plate.
The smaller plate is now moved across the larger plate , but plate separation distance is always kept the same.
My questions now are these.

1) Electron drift velocity in metals is very slow, what happens to the free electrons that form the surface charge on the lower larger plate if I move the smaller upper plate in a linear trajectory at a speed that greatly exceeds electron drift velocity in metals? Are the surface charges (electrons for example) moving along with the same speed?


2) When I move the smaller upper plate , the charge on the lower plate follows, this is called charge redistribution , does this effect is similar to a current that flows on the lower plate while the upper plate is moved?


3) Suppose I have multiple small plates in a row being moved over the much larger lower rectangular plate along the length axis of the plate, the charge on the lower plate follows the upper plates, what would I observe if I was an electron on the lower plate forming the surface charge?
If the upper plates moved with relativistic velocity would I as an electron on the lower plate observe stationary objects and charges adjacent to the stationary lower plate length contracted?

4) Can this same effect with physically moving plates against a stationary plate be simulated with a bunch of segmented plates being switched in sequence? In other words if I changed the moving upper plates with a bunch of stationary plates and switched them in sequence electronically , would it produce the same surface charge and current effects on the lower plate as with the physically moving plate?
And does the current in the lower plate resemble a current in a conductor from a stationary frame (also the frame for the lower plate is stationary)?
Thanks

 

[anuttarasammyak]

The response speed of electronic static induction is an issue. In elementary physics it is instantaneous. In circuit Slow electron drift makes light speed transmission of current. We might have similar collective motion relation in your case also.

 

[BVirtual]

I like this question as it bears on 'where' electric charge is 'stored' on the large plate. Or the small. For my answer I assume normal or typical attach points onto the plates of the leads.

What to keep in mind is electrons do not move far to store charge on the surface. Instead of a symmetric orbital probability of where to find the electron, the orbital changes shape, pushing out of the plate surface. Meaning the electron is now more likely to be found on the 'outer' side of the plate atoms, not half in and half out. The waveform probability for being found on the outer half the atom has increased, beyond 50%. Thus, there is very little electron movement from its atom. There is no current flowing between atoms. Not even from the atoms in the second layer of the plate, though those orbitals are also reshaped.

Now that you know how physically charge is stored on a capacitor plate, one can visualize what happens when the small plate is moved. No electrons leave their atom. Instead the small plate pulls at new atoms in the large plate, in the direction of motion, and reshapes those orbitals. And behind the small plate, the old reshaped orbitals resume their original shape. Easy peasy.

A similar answer is found for when a neutral metal sphere receives a single electron, increasing the charge of the sphere to -1. Where is this -1 charge stored? All atoms at the surface of the sphere have their orbitals reshaped outward an amount suitable to evenly distribute this -1 charge on the entire surface of the sphere. While there might be one atom in the -1 state, one can not tell which atom, due to this "tiny corona" forming around the entire sphere. There is symmetry, spherically distributing a -1 charge.