OU/COP>1 switched cap PS cct like Tesla's 'charge siphoning'

[Grumpy]

You would do better to charge batteries if you want power.

Better to charge caps if you want energy.

[nul-points]

You would do better to charge batteries if you want power.

Better to charge caps if you want energy.

at the moment, i just want answers! 

[nul-points]

here's an example of what i've been referring to as the 'textbook' position on the work expended in charging a capacitor:

  "once we have transferred some charge, an electric field is set up between the plates which opposes any further charge transfer. In order to fully charge the capacitor, we must do work against this field, and this work becomes energy stored in the capacitor"
...
  "The work we do in transferring an infinitesimal amount of charge from the negative to the positive plate is simply.."
...
  "In order to evaluate the total work done in transferring the total charge from one plate to the other, we can divide this charge into many small increments, find the incremental work done in transferring this incremental charge, using the above formula, and then sum all of these works..."
...
  "Note, again, that the work done in charging the capacitor is the same as the energy stored in the capacitor."
...
  "...this represents the work done on the constituent molecules of the dielectric in order to polarize them"

(excerpts from lecture notes published by Associate Professor of Physics at Texas University)

all the best
s.

[Grumpy]

When they abolished the aether, they had to cover it's purpose so they added charges to the plates, which was have already determined do not exist.

Like I said before if the energy is stored in the dielectric because if you remove the plates the energy stays in the dielectric, then where does this energy reside in a vacuum capacitor?  See first sentence above.

[poynt99]

Thanks.  Those answers are interesting, but don't answer the question.

What holds the polarization of the dielectric?  What force keeps the material stressed?

If the dielectric consists of "dipole molecules" - what "dipole molecule" is in a vacuum capacitor?

If the energy stored in the dielctirc is stored by a stretching and/or alignement of the dipole molecules of the dielectric, then what force keeps these dipole aligned?  It's not a "charge" on the plates as the plates only serve to deliever the energy and to recover it.

What if their is something else within the space between the plates of a capacitor either along with or in place of the material dielectric?  What role would this entity play in capacitance?

A dielectric between the plates of a capacitor is analogous to the "core" material used within an inductor. The dielectric and ferromagnetic cores both increase the concentration of "flux" within the component. The ability of a dielectric core to "concentrate" electric flux is the permittivity of the material, and for ferromagnetic cores it's the permeability.

A "vacuum capacitor" still has a dielectric at its core. There is no perfect vacuum and there will always be molecules floating around near the plates. In fact it you built a simple plate capacitor within a vacuum chamber and removed as much air as possible, then took a capacitance measurement, the value of its capacitance should increase in proportion to the pressure in the chamber as you reversed the process and pressurized it as much as safety would allow.

What keeps the polarization in the dielectric is equal but opposite charge matching from within the plate itself (shortage or excess of electrons) at the surface junction with the vacuum. If you could remove the plates without disturbing the vacuum molecules in their precarious state (we also have to imagine that either other vacuum charges will back-fill where the plates once were, or charge is stripped off the plates as they're removed) ), there would still be two polarized, but invisible walls/regions present. This of course would be much easier to do if the dielectric core was a solid one, but the principle is the same.

No force is necessary to keep things polarized. Net charge is always zero. It's simply charge separation, and since the net charge has neither increased nor decreased in the charging process, no net work has been done to charge the capacitor's dielectric.

.99