On Mon, Apr 19, 2010 at 6:53 PM, John Bange <jbange@gmail.com> wrote:

> On Mon, Apr 19, 2010 at 3:32 PM, Sudhir Desai <sudhir.desai@gmail.com
> >wrote:
>
> > not trying to be an ass, just trying to eliminate all trivial (for the
> > sake of explanation) variables. :)
> >
>
> Heh. Trouble is, your whole calculation comparison puts the entire mass of
> the wheel-tire unit at the perimeter, which is a non-trivial
> oversimplification. It's on the level of the classic "assume a spherical
> cow
> in a vacuum..."
> <http://en.wikipedia.org/wiki/Spherical_cow>
>
>
I understand the oversimplification, but surely the rotating mass (and
placement thereof) contributes a small portion of the overall stopping force
needed to stop a 4000lb vehicle? Or does it? If one assumes the rotating
mass is at the perimeter (worst case), what percentage of the overall force
are we looking at? I'm guessing it will be less than 10%... anyone care to
do the math with some typical figures? :-)

--
Shawn Wright