Re: Why is it "static friction?"

[Ludwik Kowalski <kowalskil@MAIL.MONTCLAIR.EDU>]

For any given v and r (up to a limit) it is an
equality. The value of mu changes when
v2/r becomes different. The, mu_s we find
in tables is the largest possible mu before
sliding begins. You are correct, mu_s*m*g
must be larger than m*v^2/r to avoid sliding.
Ludwik Kowalski

On Thursday, Nov 13, 2003, at 17:52 US/Pacific, Brian Whatcott wrote:

> At 08:29 PM 11/13/2003, Ludwik,  you wrote:
> > /// place
> > ourselves in a rotational frame of reference.
> > In that frame the centrifugal "action" force is
> > directed away from the center. And it is real.
> > The car acts on the road with the centrifugal
> > force m*v^2/r and the road acts on the car
> > with a force equal in magnitude but opposite
> > in direction. The larger the m*v^2/r becomes
> > (up to a limit) the larger is the mu*m*g (to
> > sustain the constrain imposed v and r).
>
>
> You were earlier called on equating mv^2/r
> and mu m g. The latter is an upper limit, so it
> is an  inequality which you are using.
>
>
> Brian Whatcott    Altus OK    Eureka!