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#1
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| On Thu, 16 Sep 2004 15:24:33 -0500, Old Man wrote: Bullshit. An object other than either a point mass (i.e. no dimensions, i.e. an impossibility) or a uniform spherical distribution of mass (another impossibility) exerts a force slightly different from inverse square law. Go from here and cut that bullshit. ****ing jackasses. Form of the mass counts. Shape matters. Learn the very first lessons of physics. -- fil zendash sad tomaneh mordasham sad tomaneh. |
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#2
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| "Joe Maleki" <[Only registered users see links. ]> wrote in message news:[Only registered users see links. ]... Maleki's clumsy attempt to misdirect the discussion is transparent. Yes, shape matters, a little, but total mass doesn't. The discussion isn't about the shape of massive bodies, but about an isolated system of point masses in mutual gravitational free-fall. Crudely rude, Maleki suffers from delusions of competence. Old Man is fully aware of what Maleki thinks he understands. First, for spatial coincidence of CoG and CoM points, a uniform matter distribution works, but isn't required: spherically symmetric, like that of the Earth, is sufficient. Contrary to Maleki's neophyte notions, not at all "impossible". Second, gravitational force is irrelevant. The linear acceleration of a massive body's CoM, a = a(R_cm), depends upon the location of it's CoG: in a non- uniform gravitational field, linear acceleration at the CoM is equal to gravitational acceleration at the CoG: a(R_cm) = g(R_cg) which doesn't depend upon the total mass, but depends only upon the mass distribution. Third, Maleki's problem stems from making observations from a non-inertial reference frame. The CoG of a system of gravitating bodies isn't necessarily inertial. In a non-uniform gravitational field, a massive body's CoM is in free-fall, but not necessarily its CoG. Non- uniform gravitation induces internal stress, and rotation may occur about the body's CoM if the body's CoG is displaced from its CoM. [Old Man] |
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#3
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| On Fri, 17 Sep 2004 17:52:49 -0500, Old Man wrote: Point masses! What a joke. There is no point mass. When mass is present more than gravity is involved in the problem. In a tiny lump of mass each spot of the mass is electromagnetically connected to other spots in the mass lump, and the effect of gravity on one spot unleashes a whole set of electromagnetic interactions between the "spots" and affects all the mass present in the lump. The presence of _anything_ other than a single fictitious "point mass" (or a fictitious uniform spherical distribution of mass) unleashes all these effects. Do you want to fight physics also? That's why I called you a jackass. -- arus nimitunest beraghseh migoft otAgh kajeh. |
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#4
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| On Fri, 17 Sep 2004 20:15:28 -0500, Maleki wrote: Let me use an extreme situation to show what I have in mind better. I am saying that a uniform spherical lump of one kg mass falls differently from same mass flattened to a plane of infinite size and infinitesimal thickness, because the force that the spherical lump would exert is proportional to the inverse square of the distance while the force from the infinite plane is proportional to the inverse of the distance itself, not its square. So it would fall differently. Does it makes sense? -- che kas dAde budat namAyandegi ke az ghowle mellat mozakhraf begi "Hadi Khorsandi" |
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#5
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| "Maleki" <[Only registered users see links. ]> wrote in message news:1qzjkhg1mfis8$.m3k7dkap9hfz$.[Only registered users see links. ].. . Sure it can be different. Old Man gave the answer, but Maleki snipped the lesson. With respect to acceleration, a(r), and gravitational field, g(r), a(R_cm) = g(R_cg), but for Maleki's case, the difference between a sphere and a disk of the same mass is null because R_cm = R_cg. Try a sphere and a half sphere of the same mass. [Old Man] |
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#6
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#7
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| "Old Man" <[Only registered users see links. ]> wrote in message news:[Only registered users see links. ]... [Mehram] [Mehram] [Old Man] [hanson] I liked the one wherein Mehram Maleki is pontificating, pardon me, mullahficating:...."...saying that a uniform spherical lump of one kg mass falls differently from same mass flattened to a plane of infinite size and infinitesimal thickness".... ahahahahaha.....AHAHAHAHA... ..... unfortunately, Mehram didn't finish his thought and forgot or maliciously omitted to tell us how he intends to flatten atoms "to a plane of infinite size and infinitesimal thickness" and much less where his thin 2D foil that reaches beyond the cosmic event horizons will fall to(wards)..........AHAHAHAHAHA......ahahahaha.. Mehram, sometimes you give the impression that you suffer from professional deformation due to over-intensive religious instruction....much like and akin to the myriads of little green idiots who were indoctrinated to or indoctrinated themselves with/by green bible to live by and proselytize that = "It doesn't matter what is true ... it only matters what people = believe is true ... -- Paul Watson, Greenpeace, and ...... = "A lot of environmental [political] messages are simply not = accurate. We use hype." -- Jerry Franklin, Ecologist, UoW, and... = "We make simplified, dramatic statements, and make little = mention of any doubts we may have [about] being honest." = -- Stephen Schneider (Stanford prof. who first sought fame as = a global cooler, but has now hit the big time as a global warmer) ahahahaha.....ahahahanson |
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#8
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| I think the original post simply stated "more massive bodies" . How mass is distributed will obviously affect the gravitational force. So lets rephrase the question. If two distributed masses falling in a gravitational field had the same distribution of "point" particles (e.g.molecules) but the particles had different masses, would the objects move with different velocity? That way we avoid the red herring of infinite sheets etc. David "Maleki" <[Only registered users see links. ]> wrote in message news:1qzjkhg1mfis8$.m3k7dkap9hfz$.[Only registered users see links. ].. . |
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| fall , faster , heavier , objects , vacumn |
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