|MadSci Network: Engineering|
Cheers, Look up Ziolkovsky's (Tsiolkovsky) rocket flight equation. Rockets fly because mass gets expelled at high velocity from one end - the larger the mass and the higher the velocity - the better. Pressure is involved only indirectly. http://search.biography.com/cgi-bin/frameit.cgi?p=http%3A//search.biography .com/print_record.pl%3Fid%3D11907 Basically, compressed air rocket would not work too well because the reactive mass would be too small relative to the mass of the rocket itself. If you liquify the gas you might obtain enough thrust. Water-air rockets work so well because they use relatively heavy liquid as their reaction mass. Hope it helps. A.G.E.
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