On Tue, 18 Feb 2003, kilopascal wrote: > ... > > If the velocity of the gas is in metres per second, and that is divided > by the gravitational attraction in metres per second squared, then the > resultant unit is seconds. > > Am I missing something here? > Yes. The acceleration of Earth's gravity is not involved in a proper definition of specific impulse; the element of impulse divided by mass. i.e. Fdt/mass. What, for example, is the specific impulse of a rocket motor far from the Earth? It certainly does not depend on Earth's g!
Gene.
