Re: Pushing a car uphill

[SSHS KPHOX <kphox@MAIL.CCSD.K12.CO.US>]

PHYS-L@lists.nau.edu writes:
> A good part of the problem concerns where a vehicle comes to a stop
> when parked in a forward direction. It tends to stop with one or more
> wheels on a bump - it might be a small piece of grit.
> In this case, it is helpful to roll the car backwards a little.
> (You will notice that after rolling back, it is *again* stationary,
> so arguments concerning static vs rolling friction lose their effect).

This made me wonder if the car, having sat still for a while, creates a
flattened section on the bottom that is actually greater  and somewhat
stiff, than the foot-print while in motion. Could it be that we need to
flex up the rubber a bit for easier rolling?

Ken Fox