Originally Posted by LTD02
in physics, there is a gas law where we learn pv=nrt (link below). for purposes here, as pressure increases, temperature rises. temperature is a measure of heat. heat is nothing more than vibration, well, to oversimplify. when air molecules virbrate, the temperature rises. it takes a lot more energy to vibrate the glass particles in fiberglass than the surrounding air. so, in some sense, the fiberglass sucks energy out of the air as it begins to vibrate. as a result the air vibrates less. the air temperature is lower. the internal air pressure is lower. and the subwoofer thinks there is more air in the sub. i.e., it thinks the box is larger than it is. this all happens instantaneously, so it's not like turning up the thermostat and waiting a half hour for the room to heat up. think at the speed of molecules...fractions of a second.http://en.wikipedia.org/wiki/Ideal_gas_law
LTD, I don't stand a chance of ever grasping any portion of the Wiki page, but thanks for the link anyway. I did try.
Your explanation on the other hand, helped me a great deal.
You're talking at the molecular level. Now it makes sense, what you said earlier.
As the temperature of a substance rises, the molecules within that substance vibrate with more...uh, vigor, I guess (and the electrons jump to orbital bands farther from the nucleus, thereby causing expansion of said substance).
And, anything in contact with something warmer than itself, will absorb some of that heat energy that a state of equalibrium may be reached.
And, differing materials absorb heat energy at different rates--some can absorb considerably more heat energy than another without being similarly affected proportionately physically in regards to expansion.
Or, stated differently, some materials require more heat energy to reach the same level of excitement, or expansion.
And, polyfil relieves the surrounding air of some of the heat energy it contains (in a fraction of a second).
Or, am I way off?
Okay, so that is a consideration of the compression of the air.
But, what happens during the expansion of the air? Or, is that part irrelevant?