Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site ecsvax.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!whuxl!whuxlm!akgua!mcnc!ecsvax!dgary From: dgary@ecsvax.UUCP (D Gary Grady) Newsgroups: net.physics Subject: Re: Newman's Energy Machine (2) Message-ID: <714@ecsvax.UUCP> Date: Thu, 7-Nov-85 21:47:33 EST Article-I.D.: ecsvax.714 Posted: Thu Nov 7 21:47:33 1985 Date-Received: Sun, 10-Nov-85 06:28:22 EST References: <175@tulane.UUCP> <471@iham1.UUCP> <536@talcott.UUCP> <474@iham1.UUCP> Organization: Duke U Comp Ctr Lines: 18 > It is unclear to me how potential energy contributes to an object's rest > mass. All of the cases known to me, small though that may be, show that > mechanical potential energy is due solely to the location of an object within > some force field. A wound-up clock, a charged battery, an excited atom ("It's New Year!"), a hot rock all have more mass than their lower-energy counterparts (after all, e does equal mc^2). Whether the energy they represent constitutes "potential" is a matter for definition. The hot rock's energy is kinetic, for example. You might say that the charged battery has chemical energy, but that energy is related directly to the potential energies of the electrons. Ditto for the wound-up clock or the stretched spring (in your example). -- D Gary Grady Duke U Comp Center, Durham, NC 27706 (919) 684-3695 USENET: {seismo,decvax,ihnp4,akgua,etc.}!mcnc!ecsvax!dgary