On Fri, 8 Nov 2002, James Moritz wrote:
Here is another conundrum along similar lines - you have two identical,
loss-free 1uF capacitors, one is charged to 10V, the other is discharged.
You then connect the two in parallel so the total C is now 2uF - charge
will flow from the charged capacitor into the discharged capacitor.
Assuming charge Q is conserved, and that Q=CV, the voltage must now be 5V.
But the stored energy in a capacitor =1/2CV^2, so with the single charged
capacitor, the stored energy is 1/2 x 1u x 100 = 50uJ, while with both
capacitors in parallel it is only 1/2 x 2u x 25 = 25uJ. So where has the
other 25uJ gone?
It is radiated or converted to heat. If there is no any losses (ideal
case) 25uJ is energe of magnetic field (there should be continously
oscilation if there is no disipation...)
But I do not think this is analogy to drained oil...
73 de RA9MB/Alex
http://www.qsl.net/ra9mb
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