Hi, Andrew and Group.
On Fri, 8 Nov 2002, Talbot Andrew wrote:
An oil filled capacitor consists of two plates separated by a dielectric
made of oil with a dielectric constant of 10. The capacitance is 10uF and
it is charged to 10V. The oil is drained, leaving air between the plates.
the capacitance falls to 1uF. Does the stored energy level change?. If so,
where did the extra energy come from or go to?
This is simple - hi...
When C decreases from 10 uF to 1 uF voltage increases from 10 V to 100 V
So energy E=C*U^2/2 changes from 1e-5*10*10/2=0.5e-3 J to 1e-6*100*100/2=
0.5e-2 J. Where did extra energy come from? To drain oil one SHOULD work!
Oil is ATRACTED to space betwin plates by electric field! Do drain it
extra energy is needed. For example the energy of gravity... So this is
a machine converted mecanical energy to electrical energy. It is known
some devises worked in such a way (Von de Graaf geneator, there is some
analogy)...
73 de RA9MB/Alex
http://www.qsl.net/ra9mb
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