Can anybody tell me if we have a science major on the list? ;-) Randal
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Sevak Avakians Sent: Monday, November 17, 2003 1:13 PM To: [EMAIL PROTECTED] Subject: Re: [smartBridges] Airpoint gone mad and turned into AB Hi John, Yes, the random molecular motion is due to heat and heat is the random molecular motion. They're the same thing. Heat energy is the energy of motion of molecules. You can't separate one from the other and say, "ah, this is motion" or "ah, this is heat!" You can't say that the random motion of molecules is created because of heat. It doesn't make sense. You can say that the random motion of particles is created when particles of a range of energies collide into each other and form an equilibrium. (BTW, infrared light energy is also called heat energy by some -I hope as a shorthand!- because it is radiated by those same molecules accelerating this way and that way when they collide into each other.) Friction is just a number punched into equations. The mechanism for friction is the colliding of the molecules into the surface of the aircraft. Taken at ground level, friction causes a force of the fourth power of the speed involved. At much higher altitudes, friction's force is cubed instead. If you want to know the surface temperature of an object at an ambient temperature with a constant wind velocity, you'll need to look up the material properties of the object. (Check out the indisposable "CRC Handbook of Chemistry and Physics". It will even give you the formulas to use! VERY COOL RESOURCE!! pardon the pun...) Metals, for instance, are cooler than room temp because they have a "gas" of electrons on their surface which distributes the energy from collisions more evenly. (Don't believe me? Take the temp of a metal surface compared to any other object in the same room...including the air.) Plastics and other non-conductors don't have this effect so they remain at ambient temp unless you blow on them. Sevak The PART-15.ORG smartBridges Discussion List To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe smartBridges <yournickname> To Remove: mailto:[EMAIL PROTECTED] (in the body type unsubscribe smartBridges) Archives: http://archives.part-15.org
