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From: Pioneer1 on 16 Apr 2008 13:28 On Apr 12, 1:47 pm, John Forkosh <j...(a)please.see.sig.for.address.com> wrote: > If you see a mass m > with an acceleration a, then you infer that there must be > some force F=ma somewhere, somehow, of some sort, acting on m. > But you have no clue what F is or where it comes from. I don't see it this way. Formulas describing orbits are independent of the term F. Therefore, to me orbits are independent of F. The orbit is independent of m too. Not that we don't know what force is or where it comes from but we know that, by looking at formulas, F is not a factor in orbital motion. Please let me know what's wrong with this reasoning. > Now, if that charge > q also has mass m, then you'll then see an acceleration given > by F=ma=qE so a=(q/m)E. The way I read it, this proves my point. You used F as a placeholder to obtain an equation that does not involve F. Looking at your final equation a=(q/m)E, there is no F in it. The same result can be obtained without using force. The fundamental quantity here is R/T2. This quantity is found to be proportional to E, therefore, R/T2 :: E. Constant terms are added as units to scale for measurements. You were right about units and dimensions. I didn't see it at first, but this problem is related to the use of units in physics. For instance, in R/T2 :: E both terms have dimensions R/T2. To me, this means that this is an identity, not a proportionality. If this were a computer program there would be an error because the wrong assignment operator is used. As I understand it E is proportional to 1/R2 (the intensity around charge falls off as 1/R2). So here too E is a placeholder for 1/R2. Thanks again.
From: John Forkosh on 16 Apr 2008 19:57 Pioneer1 <1pioneer1(a)gmail.com> wrote: > Formulas describing orbits are independent of the term F. You sure about that? Check any textbook discussing central forces. Maybe I'm wrong. > As I understand it E is proportional to 1/R2 (the intensity around > charge falls off as 1/R2). For point charges. How does E behave between capacitor plates? > So here too E is a placeholder for 1/R2. E and 1/R^2 have different units. Are apples placeholders for oranges? Look, if you think you know what you're doing, and have found something worth doing, then do it. I see nothing, but you don't have to convince me. -- John Forkosh ( mailto: j(a)f.com where j=john and f=forkosh )
From: Pioneer1 on 21 Apr 2008 20:46 On Apr 15, 12:08 pm, tc...(a)lsa.umich.edu wrote: > No. F is not an abbreviation, not even a meaningless one. Okay. What is it? Does it have a meaning? If it does, its meaning is not coming from observations. Then, where does it come from? > No. ma is not an abbreviation for mR/T^2. F is not an abbreviation > for ma. So why does it cancel? It's not a placeholder. It's not a temporary variable. It's not a label. It's supposed to be a "physical" quantity but it cancels out of formulas. > You might disagree with Newtonian mechanics; No. I neither disagree or agree with Newtonian mechanics. To me, Newtonian mechanics is a meaningless generalization. I'm questioning one expression: F=ma. I cannot understand the types of the symbols in this expression. Another example: Physicists call this expression a=v^2/R an "equation." To me this is not an equation, it is an identity: a= aR/R. > you should at least form a correct understanding of what it is that you are > disagreeing with. I think this is what I've been trying to do but regarding F=ma, not Newtonian mechanics. > In contrast, "GWB" *is* an abbreviation of "George W. Bush." Okay. F is an abbreviation for Force. Force is an abbreviation for that occult quality that emanates from the sun and travels the earth- sun distance at zero second by breaking all of the conservation laws of physics and then sets the earth in motion by instantaneously communicating with the earth's center about how much of itself to apply and then keeps the earth in orbit. . . It does all those fantastic things at no time at all but this force cannot be found in the formulas we use to compute the orbit of the earth. To me if a quantity does not exist in formulas then it does not govern orbits. M is an abbreviation for mass of the earth. Whatever the mass of the earth is it has no relevance in orbit calculations because mass too cancels out. Two out of three terms of F=ma cancel out of the formulas. We are left with acceleration a. No. That's a goner too. Because acceleration a stands for R/T2. R and T are the only two quantities necessary and sufficient to compute orbits. Each and every term of the fundamental equation of physics cancel out of the formulas to compute orbits. Why did physicists write three terms that cancel and made the cancelling terms the cornerstone of physics? What am I missing here?
From: Pioneer1 on 21 Apr 2008 20:48 On Apr 15, 7:39 pm, Barb Knox <s...(a)sig.below> wrote: > Note that "contact" forces are actually "occult" electrostatic ones. I don't understand why electrostatic force is considered occult. Can you explain a bit more?
From: Barb Knox on 22 Apr 2008 00:44
In article <209da200-4767-4b5b-9acc-23bd8ce8747c(a)m1g2000pre.googlegroups.com>, Pioneer1 <1pioneer1(a)gmail.com> wrote: > On Apr 15, 7:39�pm, Barb Knox <s...(a)sig.below> wrote: > > > Note that "contact" forces are actually "occult" electrostatic ones. > > I don't understand why electrostatic force is considered occult. Can > you explain a bit more? You consider gravitational attraction to be an "occult" force. What in your view makes it essentially different from electrostatic forces? -- --------------------------- | BBB b \ Barbara at LivingHistory stop co stop uk | B B aa rrr b | | BBB a a r bbb | Quidquid latine dictum sit, | B B a a r b b | altum viditur. | BBB aa a r bbb | ----------------------------- |