Stan, In your e-mail of November 11, you indicate that one of your objectives for revising the chapter "FORCE AND THE TERM WEIGHT" in your Book is to "pacify Gene." You invite comment.
I do have some suggestions. Use facts from NIST SP 330 and from NIST SP 811, with *citations of page numbers* from the latest editions of 2001 and 2000, respectively. Samples for segments of your text: "The International System of Units (symbol SI) is the preferred system of units of measurement for United States trade and commerce ..." This assertion is derived from Public Law 100-418, Section 5164 as amended in 1988. "The SI unit of mass is the kilogram (symbol kg). The mass of the kilogram is equal to the mass of the international prototype of the kilogram." "The SI unit of force is the newton (symbol N). The newton is the force which gives to a mass of 1 kilogram an acceleration of 1 meter per second, per second." "The word 'weight' denotes a quantity of the same nature as a force (newton, symbol N). The weight of a body is the product of its mass and the acceleration due to gravity at a particular location in a particular specified or implied frame of reference (i.e. in a particular coordinate system)." "Some units of mass outside the SI are the carat, grain, ounce, pound, and slug. See SP 811 for their 'definitions' as multiples of the kilogram, and for definitions of several other units of mass." "Some units of force outside the SI are the dyne, kip, and poundal. See SP 811 for their 'definitions' as multiples of the newton, and for the definitions of several other units of force." "The SI unit for lift, weight, thrust, and drag, all forces, is also the newton (N). Some units of force outside the SI are still used as units of weight. These are residue from 19th century technology." "The word 'weight' continues to be misused sometimes as a synonym for 'mass.' This careless misuse is deprecated." The remainder of the chapter could be your discussions of deviations from the SI, but I would delete much of that. Gene Mechtly. ---- Original message ---- >Date: Sun, 11 Nov 2007 15:49:50 -0500 >From: "Stan Jakuba" <[EMAIL PROTECTED]> >Subject: [USMA:39706] Past e-mails >To: "U.S. Metric Association" <[email protected]> >Cc: "Dennis Brownridge" <[EMAIL PROTECTED]>, "Matt Zotter" <[EMAIL >PROTECTED]>, "Henry A. Scarton" <[EMAIL PROTECTED]>, "Benny Leonard" <[EMAIL >PROTECTED]>, "Kverneland, Knut" <[EMAIL PROTECTED]> > > Dears: > Vacationing in Europe I missed most of the past > mail. I want to comment on just two items I noticed: > > (1) Concerning the "what is a metric bible" - unlike > the US, most nations issued just one SI (guide) > book, usually somewhat analogous the Barry Taylor's > SP 330 but thicker. Those nations have a "bible." In > the US, with its plethora of metric guides, I'd > think that the only "bible" could be the BIPM > document. (Way back, some considered the ASTM E380 > as such, but not the IEEE and other societies.) > > (2) Concerning the voting on the meaning of weight, > I was taken aback that we would think that we can > coin a single meaning. Have you, guys, ever tried to > coin a meaning with your own wife (and teenage > kids)? Why would we want to spend time on such > petty, impossible to resolve issue is beyond me > considering the presumed intelligence of this > distinguished group. > > A while ago, I sent a chapter from my book that > elaborated on the weight meanings. Pictures were > missing. I am attaching the 20 years old piece > again, this time with pictures. It is also slightly > edited to stress the unit selection and to also > pacify Gene. In addition, I am attaching an exercise > I use for getting the points across. All the > questions in the exercise are debatable, as you will > see when you try them. A discussion was the real > purpose for the "quiz", not to check the knowledge. > > Perhaps looking at the attached again and trying the > exercise will let us place the issue to rest. > > I'll be soon off for Central America, so if you > would like to comment (I wish you would), write > soon. But remember with a selection of a unit - it > depends on circumstances! List them > Thanks, Stan J. > > >________________ >b-FORCE AND WEIGHT2.doc (5950k bytes) >________________ >b-FORCE AND WEIGHT2.pdf (424k bytes)
