Dear Gene, Don't rush them on the mass vs weight issue. After all, it is only 225 years since Isaac newton clearly distinguished between mass and weight in "Principia" in 1786.
Sorry for the cynicism. Cheers, Pat Naughtin Geelong, Australia On 2011/06/20, at 23:50 , <[email protected]> <[email protected]> wrote: > The NASA John Glenn Center in Cleveland, Ohio is requesting Proposals > for a demonstration of Solar Electric Propulsion, a method of slowly > thrusting > probes along spiral trajectories into the outer regions of our solar system. > > The "specific impulse" (m/s) required for such missions can only be achieved > by electric propulsion (not by chemical rockets) fueled by solar or nuclear > energy. > > Specific Impulse (thrust times time; divided by the mass ejected by the > rocket motor) (newtons x seconds per kilogram) i.e. (kg x m/s^2) x s per kg > = m/s. > > In outdated studies, some engineers equated mass with weight and got the less > acceptable result that pounds times seconds divided by pounds equals seconds. > > Let's see if the winning proposal(s) can correctly distinguish mass and > weight? > > Gene Mechtly > > > > Pat Naughtin LCAMS Author of the ebook, Metrication Leaders Guide, see http://metricationmatters.com/MetricationLeadersGuideInfo.html Hear Pat speak at: http://www.youtube.com/watch?v=_lshRAPvPZY PO Box 305 Belmont 3216, Geelong, Australia Phone: 61 3 5241 2008 Metric system consultant, writer, and speaker, Pat Naughtin, has helped thousands of people and hundreds of companies upgrade to the modern metric system smoothly, quickly, and so economically that they now save thousands each year when buying, processing, or selling for their businesses. Pat provides services and resources for many different trades, crafts, and professions for commercial, industrial and government metrication leaders in Asia, Europe, and in the USA. Pat's clients include the Australian Government, Google, NASA, NIST, and the metric associations of Canada, the UK, and the USA. See http://www.metricationmatters.com for more metrication information, contact Pat at [email protected] or to get the free 'Metrication matters' newsletter go to: http://www.metricationmatters.com/newsletter to subscribe.
