On Thu, 5 Sep 2002 Henry Spencer wrote:
HS> Except, of course, that there are a depressing number of old (and even HS> not-so-old) publications which measure force in kg... When I was in college, forty years ago we used "kilo pond" [kp] as an unit of force in physics. HS> If one is talking about propellant flow per unit area and one must use HS> barbarous units :-), one should quote in lb/s/in^2, not lb/in^2/s. Makes indeed more sense as lb/s is the unit of a mass flow. So lb/s/in^2 is a mass flow per unit area. As we are discussing inconsistent units. Specific thrust in [s]though used in most publications came in existence from the fact that lb force was deliberately shorted against lb mass. In most newer ESA publications they use [Ns/kg]. As [N] = [kgm/s^2] you end up with [m/s] as an unit for specific trust. The number is 9.81 times that in seconds. Do not take me wrong: In my eyes ESA is also a jobs program. Hans Ulrich Ammann mailto:[EMAIL PROTECTED] http://www.spl.ch _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
