🚀 go-pugleaf

On 3 Oct, 10:52, Benj <bjac...@iwaynet.net> wrote:
> Pentcho Valev wrote:
> > You put energy to create the electric field but then, ideally, you do
> > not put more energy to maintain it, although water forms an eternal
> > waterfall outside the electric field. Consider a charged and then
> > disconnected capacitor partially immersed in a water pool, as shown in
> > fig. 6-7 on p. 112 in W. Panofsky, M. Phillips, Classical Electricity
> > and Magnetism, Addison-Wesley, Reading, Massachusetts, 1962. Water
> > rises between the plates but this does not discharge the capacitor.
> > Then, if there is a small hole in one of the plates, the SPECIFIC
> > PRESSURE will push water through it so that water will fall outside
> > the capacitor. The energy of the capacitor remains unchanged. Water
> > was lifted AT THE EXPENSE OF HEAT ABSORBED FROM THE SURROUNDINGS so,
> > as it falls, it is this energy that is released - either in the form
> > of heat given back to the surroundings or, if there is a suitable
> > waterwheel, in the form of work.
>
> Nice perpetual motion machine!  And quite different from the usual
> forms! But still won't work! The rising water will eventually
> discharge the capacitor. The field used to raise the water polarizes
> the molecules but when they leave through the hole they essentially
> discharge outside the capacitor. The charge is NOT returned to the
> capacitor. Hence it slowly discharges from the rising water. And the
> "perpetual motion" machine stops.

Ideally, there is no exchange of charge between the capacitor plate
and water. In real experiments there could be some but this is
irrelevant. That is, if the conclusion is that there is a violation of
the second law in ideal conditions, this conclusion remains valid. It
is like adiabatic isolation: ideally, there is no exchange of heat
between the system and the surroundings and the conclusions based on
this are valid, although in real experiments some heat exchange is
unavoidable.

> I do not believe the water was lifted by heat.

By what else? As it falls it releases energy: where could this energy
come from?

Pentcho Valev