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Re: Real data from real experiments.
Hi, Jack!
I would agree with your caveats, except that I specifically
said:
> >I suggested comparing the two caps to two water tanks, one
> >filled, the other, identical tank empty. Open a valve that
^^^^^^^^^^^^^^
> Also,"a total of 1/2 the original Potential energy is available" can be
> misleading because it is not clear what you mean. Do you mean that the other
> half of the energy is in losses? Note that when the tanks are unequal the
> energy in the tanks are not 1/2 the original energy. How would you calculate
> the difference in energy when the tanks are unequal?
Yes, there are losses. I suppose i have to back off a little bit
from my original statement that there really isn't any loss, only
a re-distribution of the working fluid, making the potential energy
unavailable. That doesn't make sense, in retrospect. However, if
you analyze the water analogy, at first without attempting to see
exactly WHERE the energy has gone, you'll see that it really IS gone.
> The water level in two unequal tanks would be level under certain conditions
> but not 1/2 the original height except under certain conditions of tank
> shapes. Another interesting problem. The same is true of unequal
> capacitors. The voltage across the two capacitors would be the same but not
> 1/2 the original voltage as the Coulomb equation might be interpreted.
Again, the analogy was specified with identical tanks. Indeed, if
two differently shaped tanks are used, the level will not (in general)
be 1/2 the original level. In the limit, connecting an infinitessimally
small diameter tank to a large one will make no discernable change.
Just like with capacitors. Connecting an extremely large diameter
tank will make the level (==pressure==voltage) drop far below 1/2.
Obviously, the equations governing this look exactly like those
for charge. Hell, the accepted term for the "size" of a capacitor
used to be "capacity" , rather than "capacitance"! Note, however,
that the water levels will ALWAYS be the same (OK, for open-topped
tanks of sufficient volume to prevent overflow, etc.), as will
the voltages in two caps of any relative capacitance!
> Both the energy and Coulomb equations must be properly used to arrive at
> a correct answer.
True - it's just that the energy balance is determined more as
a RESULT of the charge transfer, as the sources of "loss" are
far more complex and less determinate. Charge balance is easy
to calculate, on the other hand!
> Tesla coils must also meet the laws of conservation of energy
> and conservation of charge.
Unfortunately, also true! :{)
Dave