Re: When Physical Intuition Fails

[Brian Whatcott <betwys@DIRECTVINTERNET.COM>]

At 11:11 PM 10/27/02, you wrote:
> The recent issue of AJP posed a problem which NO physics professors (20) or
> students (67) could solve.  I wonder if anyone on this list can solve it?
> Please no peeking at the answer key.  I have already peeked so I am
> disqualified.
>
> Ignore the retarding effect of air resistance.  A rigid wheel is spinning
> with an angular speed of W0 about a frictionless axis.  The wheel drops on a
> horizontal floor, slips for some time, and then rolls without slipping.
> After the wheel starts rolling without slipping, the center of the mass
> speed is Vf.  How does Vf depend on the kinetic coefficient of friction mu
> between the floor and the wheel?
>
> John M. Clement
> Houston, TX


I am completely naive to this problem. So I will first engage physical
intuition,
 misleading though this apparently is here.
I recall the importance of not allowing tow vehicle wheels to slip on hauling
 a boat out.
I see that the minimal wheel angular speed is desired, and the end speed
will be optimized at middle values of mu, and zero for zero mu.
But that is all I initially see.

Sincerely

Brian Whatcott
  Altus OK                      Eureka!

This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.