Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 11/03/84 (WLS Mods); site astrovax.UUCP Path: utzoo!watmath!clyde!burl!ulysses!allegra!princeton!astrovax!wls From: wls@astrovax.UUCP (William L. Sebok) Newsgroups: net.misc,net.physics Subject: Re: perpetual motion Message-ID: <567@astrovax.UUCP> Date: Tue, 26-Mar-85 16:09:53 EST Article-I.D.: astrovax.567 Posted: Tue Mar 26 16:09:53 1985 Date-Received: Wed, 27-Mar-85 04:43:03 EST References: <608@vortex.UUCP> <491@spp2.UUCP> Distribution: net Organization: Princeton Univ. Astrophysics Lines: 20 Xref: watmath net.misc:7665 net.physics:2320 > While I tend to agree with Lauren that there is a lot of garbage being > passed around as truth, I have to wonder why our cars aren't powered > by liquid hydrogen (a non-polluting fuel) rather than gasoline. > Jeff Hull {decvax,hplabs,ihnp4,scdrdcf,ucbvax} You have got to be kidding. Liquid hydrogen is DANGEROUS. At atmospheric pressure it boils at 20 degrees Kelvin == -253 degrees Celsius one of the lowest boiling points known next to helium. You have to allow blowoff from a container (pressurized or not) container to keep it from blowing up as the liquid boils and the pressure builds up. The blowoff is VERY flameable. It took quite a bit of effort for the space program to work up the technology to keep the liquid hydrogen fueled rockets from blowing up on the pad. I would be very leery of having it in general by any other than very highly trained people. Pressurised hydrogen though ... well, maybe. -- Bill Sebok Princeton University, Astrophysics {allegra,akgua,burl,cbosgd,decvax,ihnp4,noao,princeton,vax135}!astrovax!wls