Wizard, Yes, F = ma can be used in Imperial. But using it is a personal choice. And some branches of science have used ifp far into the last century.
>From Rowland's Dictionary of units under the letter P. http://www.unc.edu/~rowlett/units/index.html British Gravitational has this unit of force (comparable with the kgf): pound force (lbf or lb) a traditional unit of force. Traditional measuring systems did not distinguish between force and mass units. A force of one pound is simply the gravitational force experienced at the Earth's surface by a mass of one pound. To compute this force, we multiply the mass by the acceleration of gravity, following Newton's law F = ma. Since one pound of mass is 0.453 592 kilograms and the acceleration of gravity averages 9.806 65 meters per second per second at the surface of the Earth, one pound force equals the product of these two numbers, 4.448 221 615 newtons. The symbol lbf should be used for the pound force to distinguish it from the pound of mass British Absolute. It has a pure unit of force, just as SI has the newton. It is used far less than the lbf. poundal (pdl or pl) an English unit of force used in engineering. Since traditional measuring systems, including the English system, did not distinguish between force and mass units, the poundal was defined to provide a unit clearly measuring force rather than mass. One poundal is the force which accelerates a mass of one pound at the rate of one foot per second. Since the acceleration of gravity averages about 32.174 ft/sec2 at the Earth's surface, one poundal is about 1/32.174 = 0.031 081 pound of force. One poundal is also equal to approximately 0.138 26 newton, or 13 826 dynes. The newton, the SI unit, is now the preferred unit of force in engineering and technical work. The poundal was invented in the 1870s by the British mathematician James Thomson, who also named the radian. It seems that the science of thermodynamics has used a lot of Imperial/USC until late into he last century. Mesures et Controles Industriel, 1958-05, p. 351. This French technical magazine waged a courageous campaign against the infiltration of ifp in France for decades. The contagion which shows too well on a website like the Maporama one and in Jacques Cousteau's films, has been present for decades, even boosted for some time since 1944/45. And so is the struggle against it. "La situation est beaucoup plus grave... Cette ann�e (1958), � l'Universit� de Lille, un cours de transfert de la chaleur est profess�e dans la section 'G�nie Chimique' en utilisant exclusivement les unit�s anglo-saxonnes (livres, pieds, etc) et employant les notations anglo-saxonnes (en particulier le point entre les unit�s et la decimale, et la virgule entre les milliers et les centaines). La m�me personne professe un cours de thermodynamique � la Facult� Libre de Lille en utilisant les m�mes unit�s et les m�mes notations". "The situation is much more serious.... This year (1958) a course in heat tranfer is being taught at the section 'G�nie chimique' at Lille University, using exclusivily Imperial/US measuring units (feet, pounds, etc.) and using the UK/US notation of numbers (the point as decimal sign, the comma as separator between thousands or hundreds). The same person is also teaching a course in thermodynamics using the same units and the same notations at the Free Faculty at Lille University". If ifp could not be used in science and high technology at all it would have collapsed in the 19th century. See also the last sentences of USMA 16859. There would be no USMA and no USMA list server. And before metric came, science used inches, feet and pounds in all their local varieties. Last but not least, I found this on one of the UKIP forum: Compulsory Metrication. http://www.ukip.org A lot of people on their forums claim to be young, or/and claim to have a scientific background, while being anti-European and anti-metric! Philip Moore ( - 131.111.237.176) on Sunday, May 14, 2000 - 01:30 pm: As a 20 year old science student at Cambridge University I have been exposed to "metrication culture" all my life. We are not taught Imperial Measures anymore, and this is a crying shame. I for one taught myself Imperial measures and used them to pass my Physics A-Level! The Imperial System is more practical because its units were developed from use, rather than by Committee. It requires greater numeracy than Metric, but this is a skill to be encouraged! It is part of our culture and history and should not be replaced by a soulless alternative. I don't suggest we outlaw Metric - that would make me as bad as the EU - but let those of us who want to do so use Imperial! Han ----- Original Message ----- From: "Wizard of OS" <[EMAIL PROTECTED]> To: "U.S. Metric Association" <[EMAIL PROTECTED]> Sent: Friday, December 28, 2001 8:30 PM Subject: [USMA:16897] Does science work with imperial at all?? I am wondering how physical, math. or chemical calculations are possible without SI? personally, I cant imagine, e.g. F = m a seems impossible with imperial!
