File talk:Newton'sLawsOfMotion.jpg

Latest comment: 17 years ago by Ancheta Wis in topic P not = mv

P not = mv edit

The first law (conservation of momentum) does NOT state that F=mv but rather that P1 = P2

I appreciate your restatement of the first law.
I see at least two typos in these two lines. If you view the first law as a definition, it is correct prima facie, and the heading of the section here is incorrect; P is not the same as F, in any event -- thus the typo on the second line. If you view the first law as a conservation law, then it is a statement about matter, and holds for things like hard spheres, but not necessarily for other types of matter (think of a millimeter steel ball-bearing colliding with an earth-sized ocean of mud).
I really think of the first law Objects in motion tend to remain in motion; objects at rest tend to remain at rest (until acted upon by an outside force) from my school days. That is what I consider so valuable about this content, as it is a restatement in equation form, coming from Sander Bais The Equations. --Ancheta Wis 15:08, 15 March 2007 (UTC)Reply