Motion
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From: Herman Trivilino on 20 Sep 2005 19:08 "Don1" <dcshead(a)charter.net> wrote ... > The acceleration increases, and the force is as constant as I can keep > it, but lessens as the sled gains speed. The acceleration *decreases*. The force does indeed decrease for the very reason you stated. When the net force decreases, so does the acceleration. Net force and acceleration are proportional, with their ratio equal to the mass of the wagon. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =----
From: Herman Trivilino on 20 Sep 2005 19:12 "Don1" <dcshead(a)charter.net> wrote .... >> >> And, as I said, you could improve on your formula [...] >> >> by adding a third order term. Would you like >> >> me to do that for you? >> >> >> >> >> > Yeah. Then maybe I'll know what your talking about. >> s = (v_o)t + (1/2)(a_o)at^2 + (1/6)jt^3. > Clear as mud Herman. Well, I did try. I guess the case of nonconstant force (and therefore nonconstant acceleration) is beyond you. In this case, you should stick with s = (v_o)t + (1/2)at^2 and pretend it applies to all cases, even those that are beyond you. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =----
From: odin on 20 Sep 2005 19:41 > The force does indeed decrease for the very reason you stated. When the > net force decreases, so does the acceleration. Net force and acceleration > are proportional, with their ratio equal to the mass of the wagon. Did you get that Don1? Like the man said... force and acceleration are proportional, with their ratio equal to the mass. As in: F=M*A ...ring any bell? Can we now move on to the next century? How about some electricity and magnetism for starters? Please?
From: TomGee on 20 Sep 2005 20:03 Randy Poe wrote: > TomGee wrote: > > Randy Poe wrote: > > > TomGee wrote: > > > > Sam Wormley wrote: > > > > > Newton is much more precise > > > > > http://scienceworld.wolfram.com/physics/NewtonsLaws.html > > > > > > > > > > 1. (Law of inertia): A body at rest remains at rest and a > > > > > body in motion continues to move at a constant velocity > > > > > unless acted upon by an external force. > > > > > > > > > > > > > > Well, well, Worms, you're starting to support your beliefs with actual > > > > excerpts from your websites! Very good, keep it up. > > > > > > No matter what well-known fact you choose, somewhere on the > > > internet is somebody who disbelieves in it and writes volumes > > > on his (occasionally her) disbelief. > > > > > > > According to your buddy PD, though, the 1st law includes a claim that > > > > the body has no internal force to keep it in motion. Did you leave > > > > that out, or don'tcha agree with PD? > > > > > > That's correct. There is no force that keeps bodies in motion. > > > Forces only act to change motion. > > > > > > > > So you agree with PD and Worms. > > And Newton, yes. > > Yet Newton does not say that at all above where Worms offers Newton's 1st law. Someone needed to infer that and told everyone Newton said that but no one has been able to find where Newton said that. In fact, in one translation I discovered, it has Newton referring to an inherent force moving a body in a uniform motion as per his law 1. > > > What else is new? > > Certainly not that. It's centuries old. > > > They only believe > > that because they were taught to believe that. > > Well, also because it works as a valid model of reality. > > But it doesn't work well because it has matter moving without any force at all to propel it even while it has the energy of motion which is gained from a body's momentum. That is the energy excluded from his shortened version of E=mc^2+(energy of motion) in order to cancel out that energy from all the bodies involved in calculating the amount of energy in a given mass which is "at rest". It's a false model simply because Newton's 1st law was corrupted in its translation and even in those where he does not state that no force is needed for the object in his 1st law, others like you have come to believe he did say that, due to us been taught that over and over. > > > > Anyone with a real > > brain would be able to support such a wild statement, but I see you > > offered none, so that's just your opinion. > > OK, fair enough: what keeps the planets going, along with > every satellite and chunk of space junk, if they need > propulsion in order to keep going? > > A question is not an opinion. Support the opinion you gave us. > > > > > > PD claims such accelerations do not amount to a change in kinetic > > > > energy. Do you agree or disagree? > > > > > > You are misreading something. A change in speed constitutes > > > a change in kinetic energy. > > > > > > > > No, no misreading. Read it for yourself word for word in this same > > thread. > > Can you quote the relevant passage? > > Yes, but what's in it for me? I mean, what effect will that have on our discussion here between you and me. Will you agree with me against PD? Will you denounce his silly idea(s) as I do? Or will you just find something else to avoid doing that? > > > > > Perhaps you garbled a description of circular motion, in > > > which the force acts perpendicular to the velocity. In that > > > case, the acceleration results in a change of direction, > > > but not of speed, and the kinetic energy is constant. > > > > > > > > No, no garbling by me. > > If you garbled the meaning, you would hardly be the one to > know, would you? You'd only have your garble as reference. > > You did not say I may have garbled the meaning; you said I may have "garbled a description of circular motion", but I see what you mean. > > > > > So the force in 2. above is different from the force of bodies striking > > > > each other? > > > > > > When bodies strike each other, the forces obey Newton's laws, > > > including the third law. > > > > > Then PD must think those laws apply only to bodies in classical physics > > and not to quantum particles. > > I've seen nothing in PD's writing to indicate such a view. > > Yes, you have. I just pointed out that he defines a force differently for classical physics than he does for quantum particles. In one a force only "pushes" and in the other, it only "pulls". > > > > > > In 2., the force makes a body move in the same direction > > > > of the force, > > > > > > The acceleration is in the direction of the force. That may or > > > may not cause motion toward the force. Generally not. If > > > something is moving past you and you give it a kick as it > > > goes by, it won't change direction and start going straight > > > out from the direction of your kick. It will still have a > > > component due to the original motion. > > Well, I didn't say that; it's claimed that's what Newton said. > > > > > > > > Yes, I know, but PD does not know that. > > I've seen nothing in PD's writing to indicate such a view. > > In fact, you were putting your garbled interpretation on > something PD just wrote, which did not resemble in any way > what you are saying. > > Oh, and what was that and where's your supporting statements for that wild charge against me? > > > > > > but in 3., the force of one body makes the other move > > > > away from it. > > > > > > No. That is really garbled. > > > > > > > > No, it's not, read it up above, it's exactly what PD said. > > I read it. > > > If it > > proves anything it's that his brain is garbled. > > Words are written. They are then paraphrased by you. I agree > with the original words. I find yours seriously garbled. > Hmmm... where did the communication error occur? > > Ok, we have proof that PD's brains are garbled; you agree with him but you say my words are garbled but you offer no supporting statements for that opinion, nor against the proof we have, so if your brain is garbled you would hardly be the one to know, right? You only have your garbled brain as reference. > > > > > If A pulls on B, then A gives an > > > acceleration of B toward A. > > > > > Yes, but PD did not say, "IF A _pulls_ on B,...." He makes no > > distinction of pulling or pushing. > > The principle applies in either case. > > Not if there's no "IF" to it. Without it, the statement is grammatically incorrect. > > > If A pushes on B, then B pushes back. If you sit on the floor, > the floor pushes back with enough force to support you. If > it did not, as happens if you are sitting on a weak tree > limb, or in midair, you fall. > > > > That's law number 2. At the same > > > time, A is pulled toward B. That's law number 3. The fact that > > > A is pulled toward B does not contradict the fact that B is > > > pulled toward A. > > > > > No, that's not law number 3. > > Yes it is. > > > Now you're getting confused just like PD. > > Words are written, then paraphrased by you. I agree with the > original words, I disagree with the paraphrase. Where did > the communication break down? Hmmm.... > > > > If you hit a piece of wood with your fist, you might dent > > > the wood (law #2). That does not prevent the wood from denting your > > > hand at the same time (law #3). > > > > > No, not so. Both relate to the 3rd law of action/reaction., > > The denting of the wood happens because the forward force you > impart to the surface gives forward motion to the surface. > > Yes, and that is explained by the 3rd law of action and reaction. > > > The relation between force and acceleration is certainly > NOT law number 3. > > Another wild claim lacking support - a mere opinion.
From: Herman Trivilino on 20 Sep 2005 21:26
"Don1" <dcshead(a)charter.net> wrote .... >> >> And, as I said, you could improve on your formula [...] >> >> by adding a third order term. Would you like >> >> me to do that for you? >> >> >> >> >> > Yeah. Then maybe I'll know what your talking about. >> s = (v_o)t + (1/2)(a_o)t^2 + (1/6)jt^3. > Clear as mud Herman. Well, I did try. I guess the case of nonconstant force (and therefore nonconstant acceleration) is beyond you. In this case, you should stick with s = (v_o)t + (1/2)at^2 and pretend it applies to all cases, even those that are beyond you. ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |