Re: Friction

["Rick & Bea Tarara" <rbtarara@sprynet.com>]

My interpretation of the low mileage tires has always been to reduce
rotational KE.  I assume that by having the minimum thickness and
hence mass at the radius of the tires, the minimum amount of energy
goes into the rot KE and hence the max into translational KE.  The
trade off may be small, but since these cars have to be refueled every
100 miles or so anyway and the tires can be changed within the
refueling time frame, the gain in speed is worth it.  Note that in
other racing, Grand Prix for example, where there is only one or even
no scheduled pit stops, tires are used that can go the distance.  The
tollerances in professional racing are VERY tight--so every little
edge helps.

Rick Tarara

> From: Daniel L. MacIsaac <danmac@physics.purdue.edu>
>
> How far do professional racers get on a set of professional racing
tires, 
> anyway?  I suspect the design of those tires is such that they wear
VERY 
> quickly, and extrapolating the wear behaviours/characteristics of
those 
> tires to everyday driving situations might be inappropriate.  How
many sets
> of tires are used by one car in the Indy 500?  They certainly seem
to change
> them a lot more often than I :^).