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Ok, so the force page is going down the same path as the tensor page. Which is not good. I propose the following structure:

• brief remarks indicating the force is not an easy thing to define or understand, and that Real Smart People have thought about for a long time.

• elementary definitions useful for mechanics, such as F = ma, with examples,

• an explanation of rational mechanics and the difficulty of defining force rationally. This would Truesdell and Nolls work specifically, with a bow to Hilbert for granting mathematical legitimacy. The Hamel's work should be dealt with here also.

• discussion on the new configurational forces schemes of Morton Gurtin and Gerard Maugin, and why they are different, and why it matters.

Whew.

I can take on the Gurtin stuff, I have his monograph.

I think you miss the point that F=ma is the definition of F, and definitions by themselves have no physical content. The related physical content is the reification of this defined concept of force. Please be sure you undestand this distinction before you edit the page further.

In most expositions of mechanics, force is usually taken as a primitive, without an explicit definition. Rather it is taken to be defined implicitly by the (often vague) presentation of the theory within which it is contained. Various physicists, philosophers and mathematicians, such as Ernst Mach, Clifford Truesdell and Walter Noll have contributed to the intellectual effort of obtaining a more rational, non-circular, and explicit definition of force.

I toned this down a good deal. While I haven't read these authors, there are many contexts in which an implicit definition is both useful and logically rigorous. In math, for example, there are many "undefined terms". (In modern formulations of Geometry, terms like "like" and "point" are such terms; they're "defined" only implicitly, by how they're used.) Thus there's no need to link implicitly defined terms to circularity or irrationality. --Ryguasu 21:39 Nov 19, 2002 (UTC)

I have disambuated Force into Force (physics) and Force (law) and started going back and sorting out the links, but there are so many of them that I need some help. Will anyone who's willing to help please use the 'what links here' on Force to find articles linking here and change those links to the right article; if the topic is one of the many that are a definition of something in physics that don't start out with that qualifier, please add "In ], " at the beginning, and don't forget to lowercase the next letter, which used to be the initial capital. (If you run across a link to a different meaning of "force" than in physics or in the law, please either leave it alone, so it comes to this disambiguation page, or define the new one with a parenthetical title and make it go there.) Thanks for any and all assistance. -- isis 09:53 Oct 26, 2002 (UTC)

I'm not sure we should relegate physical force to a disam-type title. I suspect it it by large the most commonly-used meaning of "force" (in terms of links on wikipedia); maybe it should get priority like Newton does. -- Tarquin 10:19 Oct 26, 2002 (UTC)

Please remember that Misplaced Pages:Misplaced Pages is not a dictionary. If there really isn't very much to be said about the alternative definitions of "force", then there's no point making a disambiguating page! -- CYD

I think there's a possible encyclopedia article about the concept of force in law, but I agree that by far the overwhelming number of links will want force (physics), so I suggest that force (physics) redirects to force and that that article in its first sentence points out that force (law) exists as well. This is what we typically have been doing if one meaning is much more common than another. AxelBoldt 18:47 Oct 26, 2002 (UTC)

Moving it back to "Force". -- Tarquin 16:50 Jan 15, 2003 (UTC)

Shouldn't F=MA be F=mã or F=ma?

And shouldn't

F = Limit as T goes to zero of (mv - mv_o)/T

be something like

${\displaystyle {\vec {F}}=\lim _{\Delta t\to 0}{m{\vec {v}}_{t+\Delta t}-m{\vec {v}}_{t} \over \Delta t}}$

Haven't changed that part, in case everyone happens to disagree with me.

LT_EΧed 3 lines, using bold for vectors like the articles here seem to do, instead of vector arrows (or underline for typewriters and arrowless document formats), as I thought was normal.

-- Cyp 20:53, 28 Jan 2003 (when I wrote this, but the wikipedia seemed to be broken when I tried to post this.) (Now 0:24, 29 Jan 2003)

Arrows / underlines tend to be used in handwritten documents. Convention for print is bold, AFAIK; older books use arrows -- Tarquin 00:21 Jan 29, 2003 (UTC)

I note that at least one major physics text book has returned to arrow notation for vectors. Namely, the sixth (and seventh?) edition of Fundamentals of Physics, by Halliday, Resnick and Walker. -- Jason Le Vaillant 08:58 Feb 9, 2004 (UTC)

Whether they use boldface or arrows to indicate that they are vectors, that F and a should still always be italic as well, should they not? I haven't changed this yet, but likely will when I make some other changes, unless anyone disagrees on this point in which case we can discuss it. Gene Nygaard 12:41, 12 Dec 2004 (UTC)

Combining Forces

"The more powerful force cancels out the less powerful; a resultant force is produced."

It's not like the "less powerful" force is completely ignored - both forces will have an influence on the net force. That sentence is misleading.

Brianjd 06:36, 2004 Jun 17 (UTC)

Why Forces ARE fundamental in Physics

The view (expressed at the beginning of the article) that energy and momentum are more fundamental physical quantities than forces is simply wrong. Energy and momentum are merely quantities associated with the path and time integrals over the force field respectively and are in principle not required in physics at all (one can happily integrate any equation of motion without ever mentioning energy and momentum).
The mathematical Hamilton and Lagrange formalisms in theoretical physics suggest the opposite, but they implicitly use forces as well because they can not be defined without potential functions which in turn depend on force fields.
The school approach of emphasizing the role of forces is therefore not only didactically but also factually correct. (for related aspects see my website http://www.physicsmyths.org.uk ).

OK, could you precisly define force? I don't know any exact definition. Already Newton knew that force had problem with a correct definition. 130.230.12.39 08:23, 24 Sep 2004 (UTC)

"Imperial newton"

The stuff that was on this page about an "imperial newton" was about the biggest piece of nonsense I've ever seen in quite some time. Not because there is no such unit--but nobody calls it by that name.

The unit that was called an "imperial newton" here is, in fact, the poundal. It already had its own Misplaced Pages entry. It can be found in any decent dictionary. It is part of the very first coherent subset of English mechanical units, the absolute foot-pound-second system introduced back in 1879.

Note that newtons did not exist in 1879. That unit was only invented 25 years later, and it wasn't officially accepted by the CGPM as the name for the mks unit of force until 1948--nearly 70 years after the poundal was invented. (However, dynes are older than poundals. They are the units of force in coherent cgs systems.)

Just go look at any physics or engineering textbook from the first half of the 20th century--there's a pretty good chance you will find it using poundals. For example, the slug was invented in 1902 by the English physicist A.M. Worthington. Yet 18 years later, in a later edition of the little book in which he introduced the slug, he was still telling us in A.M. Worthington, Dynamics of Rotation: An Elementary Introduction of Rigid Dynamics, London, New York, Bombay, Calcutta, and Madras: Longmans, Green, and Co., 1920, p. 9:

"British Absolute Unit of Torque.–Since in the British absolute system, in which the lb. is chosen as the unit of mass, the foot as unit of length, and the second as unit of time, the unit of force is the poundal, it is reasonable and is agreed that the British absolute unit of torque shall be that of a poundal acting at a distance of 1 foot, or (what is the same thing, as regards turning) a couple of which the force is one poundal and the arm one foot. This we shall call a poundal-foot, thereby distinguishing it from the foot-poundal, which is the British absolute unit of work."

Note also that slugs did not exist in 1879. They are also a 20th century invention.

There are lots of other problems in the same neighborhood of the article; I'll work on them, too. Gene Nygaard 08:12, 11 Dec 2004 (UTC)

In other words, it would have made a lot more sense to never call the newton by its own name, instead only calling it the "metric poundal," than it did to call the English unit an "imperial newton" without even giving its own name. Gene Nygaard 08:22, 11 Dec 2004 (UTC)