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Re: Charge stored in Dielectric? Not really - MISCONCEPTION



Original poster: "Antonio Carlos M. de Queiroz" <acmq-at-compuland-dot-com.br> 

Tesla list wrote:

 > Original poster: dhmccauley-at-spacecatlighting-dot-com

 >...
 > However, this is not correct.
 >...

Nice experiments. But I would not say that the concept is completely
wrong. The -charge- in a high-voltage capacitor is really in the
surface of the dielectric, and, as you correctly explain, even if
the voltage is initially not high enough to cause breakdown between
the plates and the dielectric surface (supposing that they are not
in perfect contact), when you disassemble the capacitor the voltage
grows and most of the charge sparks to the dielectric surface.
The energy becomes really stored in the dielectric, but not by
some mysterious reason.

I look with some suspicion the experiments with oil. Any oil is
always a much poorer insulator than dry air, and I don't see how
an experiment using static charges may work under oil. All the
charge would be drained immediately through the oil. This may
explain why the disassembly of the capacitor under oil didn't
result in any left charge (it leaked through the oil). When you
reassembled the capacitor uder oil, there was no increase in voltage,
and so some charge remained.

Another fact frequently mentioned with this experiment is that
"the dielectric can be touched and nothing happens". This is
simply false. If you touch simultaneously both sides of the
dielectric you are reassembling the capacitor with your hands
as plates, and you receive a discharge and discharge the
dielectric.

Antonio Carlos M. de Queiroz