On 11/13/2003 04:02 PM, Ludwik Kowalski wrote:
> Why do we say that the m*v^2/r (acting on a car) is
> the force of static friction?
I prefer to call it quasi-static rolling friction.
But calling it static friction is not wrong, since
it behaves more like static friction than dynamic
friction, as discussed at http://www.av8n.com/physics/car-go.htm#sec-friction
> I think of static friction as a "responding" force. For
> example, a crate pulled to the right (by a rope) will
> experience a responding force (from the floor) directed
> to the left.
That way of thinking anthropomorphises the force,
which is usually irrelevant and sometimes misleading.
F does not "cause" ma, and ma does not "cause" F,
for reasons discussed at http://www.av8n.com/physics/causation.htm
On 11/13/2003 04:40 PM, Ludwik Kowalski wrote:
> I have no doubt that friction has something to do
> with turning. Without friction a car would continue
> to move along the straight line, no matter how its
> wheels are turned. But this alone does not justify
> the statement that m*v^2/r=mu*m*g.