Re: Rolling, Static, and Kinetic Friction

[Raacc@aol.com]

In a message dated 96-07-12 19:22:25 EDT, Richard L. Bowman writes:

<< So going downhill, kinetic friction is uphill and static friction is
 downhill. >>

Richard,

Are you saying that the static friction from the incline on the tire is down
hill?  Wouldn't this cause a torque, on the wheel, against the rotational
motion of the tire as it goes down and therefore, wouldn't the tire be
slipping?  Hence, the frictional force would not be static.  I've always
thought of frictional forces being forces that try to prevent sliding between
two surfaces.  For the wheel not to slip on the incline, wouldn't the static
friction on the wheel, at the point of contact, be uphill?

 rac
 
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