
In article <[email protected]>,
Lester Zick <[email protected]> wrote:
> On Mon, 25 Sep 2006 16:13:24 0600, Virgil <[email protected]> wrote:
>
> >In article <[email protected]>,
> > Lester Zick <[email protected]> wrote:
> >
> >> On Mon, 25 Sep 2006 12:55:00 0600, Virgil <[email protected]> wrote:
> >>
> >> >In article <[email protected]>,
> >> > Lester Zick <[email protected]> wrote:
> >> >
> >> >> On Wed, 20 Sep 2006 10:42:56 0700, Lester Zick
> >> >> <[email protected]> wrote:
> >> >>
> >> >> >On 14 Sep 2006 18:47:35 0700, [email protected] wrote:
> >> >> >
> >> >> >>yeah, prove that geometrically using calculus or
> >> >> >>just algebra . . .
> >> >> >
> >> >> >Where m1 is aggregate gravitationally attractive mass
> >> >> >in a disk of uniform thickness and density in which the
> >> >> >amount of gravitationally attractive matter ~ area=rrpi
> >> >> >times unform thickness d:
> >> >> >
> >> >> >As a function of radius r the aggregate force of gravitational
> >> >> >attraction will be:
> >> >> >
> >> >> >F=Gm1m2/rr=Gm1(rrpi)m2/rr=Gm1(pi)m2 and
> >> >> >
> >> >> >dF/dr=0 and gravitationally attractive force is constant as a function
> >> >> >of radius r: hence tangential velocity of all m2's will remain
> >> >> >constant as a function of radius r.
> >> >> >
> >> >> >QED.
> >> >>
> >> >> I think that in light of the foregoing the appropriate question to ask
> >> >> is not why the velocity curve in Andromeda is flatter than expected
> >> >> but why the velocity curve in Andromeda is not flat to begin with?
> >> >
> >> >Because "F=Gm1m2/rr=Gm1(rrpi)m2/rr=Gm1(pi)m2" is based on some false
> >> >assumptions, among others, that any part of Andromeda further from the
> >> >center than r has no effect.
> >>
> >> That's your false assumption not mine.
> >
> >The whole of that equation and how it applies to Andromeda are Zick's
> >assumptions, not mine.
>
> Not quite. I don't assume it applies to Andromeda; you do.
Not me. I know quite well that it does not apply to Andromeda.

