My point was that I don't understand where the confusion is as to where the
heat comes from in filling a scuba tank. You are cramming a whole crapload
of molecules into a confined space and it makes heat. If you cram those
molecules into that space quickly (with respect to how fast you can
dissipate that heat) you get a VERY hot tank. This formula just explains it
better to me, though it doesn't seem to satisfy some as an explanation. It's
the same as a deisel engine except that rather than increasing the number of
molecules of air, the deisel decreases the volume of a fixed number of
molecules. It does it rapidly, so there's no time to dissipate the generated
heat through the cylinder walls, and the air heats up enough to ignite the
fuel when it's added by the injector. If you filled up the scuba tank very
slowly, giving it time to give up its heat to the surroundings (they're
filled in a water tank, no?), then it would not get so hot. I'm guessing
that they are filled from a pressurized tank. That TANK will get cold due to
the decreasing number of molecules in it as the scuba tank fills.

I guess I just don't get where all the confusion comes from. What do scuba
tanks get filled to? Something like 2 or 3 THOUSAND psi, no?

mike

"Matt Whiting" wrote in message
...
mike regish wrote:
Not a thing.

mike

Yes, so what is your point with respect to temperature as a measure of
energy?

Matt

OK, I was trying to figure out the connection and didn't see one. :-)

Matt