Re: [Phys-l] CENCO car-and-track apparatus

["Dan Crowe" <Dan.Crowe@Loudoun.K12.VA.US>]

My guess is that the dominant factor is a frictional torque at the axle,
rather than rolling resistance at the surface over which the wheel is
rolling.  The frictional torque would be due primarily to kinetic
friction between the axle and its bearing.
 
Daniel Crowe
Loudoun Academy of Science
dan.crowe@loudoun.k12.va.us 

> > > ccrook@pen.k12.va.us 6/1/2007 10:56 AM >>>
I realize that an "improved" version of this apparatus is available, 
but the big improvement was to try to reduce friction.  However, I 
use this apparatus for a lab whose main goal is to measure the force 
of friction and calculate the coefficient of friction, so the older 
apparatus is really more appropriate.  (OK, don't shoot!  I realize 
it is actually rolling resistance...)