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Re: Car acceleration



John Mallincroft..

I am not "simply, patently, grossly wrong". John
Denker's explanation today (2/4/02)gives an excellent
analysis of static friction that should be VERY
helpful to all of us!

HERB GOTTLIEB FROM NEW YORK CITY
(Where we are not always right but NEVER simply, patently, grossly wrong)


herb
On Mon, 04 Feb 2002 06:44:28 -0800 John Mallinckrodt
<ajmallinckro@CSUPOMONA.EDU> writes:
STATIC friction occurs only when the car's velocity is zero.
...
Herb Gottlieb from New York City
(Where most of our physics textbooks ignore static friction)

Herb,

This is simply, patently, grossly wrong. Whenever there is a
nonnormal component of the contact force between two objects that
are not **slipping** we have, by definition, "static friction."
Trust me on this: Your car would not work *at all* without
frictional contact with the road and you are almost always in
*serious* trouble when that friction stops being of the static
variety.

John Mallinckrodt from Pomona
(Where we think textbooks in New York ought to start treating
static friction correctly.)



Herb Gottlieb from New York City
(Where it's nice to live but I wouldn't
want to be a tourist here)
herbgottlieb@juno.com