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-----Original Message-----
From: Hugh Haskell [mailto:hhaskell@MINDSPRING.COM]
Sent: Monday, February 03, 2003 2:09 PM
To: PHYS-L@lists.nau.edu
Subject: Re: There's work, and then there's work
At 10:28 -0800 2/3/03, David Rutherford wrote:
capacitor. But
I don't know much about superconductivity, but shouldn't you be able
charge the capacitor in the absence of resistance (superconducting
circuit). Then, since the energy loss doesn't depend on R, you would
still have to get 1/2 CV^2 for the energy stored on the
where does the other 1/2 CV^2 energy go, in this case? Or maybe theactually CV^2, not
energy stored on the capacitor in the first place is
1/2 CV^2, even in the presence of nonzero R.Even if you have superconducting wires and no resistor in the
circuit, we still, as far as I know, don't have superconducting
batteries. Every battery has an internal resistance, and in the
absence of resistance anywhere else in the circuit, the (CV^2)/2 that
is lost to the resistor, will be lost to the resistor in the battery.
Sorry, there ain't no free lunch.
Hugh
--
Hugh Haskell
<mailto:haskell@ncssm.edu>
<mailto:hhaskell@mindspring.com>
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