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Re: misconception re ice melting under skates

At 14:49 3/2/98 -0500, Herb Gottleib wrote:
--------- Begin forwarded message ----------
State University of New York at Stony Brook
Stony Brook, NY 11794-3800

Clifford E Swartz
PHYSICS
516 632-8175 991022
02-Mar-1998 10:49am EST
FROM: CSWARTZ
TO: herbgottlieb@juno.com ( _herbgottlieb@juno.com )

Subject: RE: : Re: misconception re ice melting under skates

Dear Herb,
There's a 2/3 page explanation of the ice skating
problem on p 93 in the book that Tom and I wrote,
including a reference to an article on the subject
in TPT, 30,495 (1992). Rather than typing it out on
the computer, I could send a fax or hard copy if you're
interested. One of the fascinating features of the
explanation is that Faraday first noticed, or suggested,
the effect.
... Optimum
temperature for low friction and fast skating is at
about -7 degrees, because there is a competing factor
of hardness of the ice.
Cliff

Lacking ready access to either of Cliff's references, I would be
pleased if Herb could shoot me a hardcopy (or electronic copy via
any any image method) of that page 93.
I see he alludes to the loss of 'hardness' near melting.
I expect a materials person would talk about the reduction in
yield strength, the creep and bearing failure visible in a range
of materials nearing melting.

I was surprised that I had overlooked Faraday's observation
of the surface change of state. Perhaps Cliff can cite this reference.

In this context, I was tempted to observe that the various equations
for perfect gas which have lately threaded through PHYS-L all seem to
break down near changes of state - this area being still somewhat
mysterious I suppose.

While browsing Faraday's researches in connection with the electric
field effect on a water column, (in connection with yet another
PHYS-L thread) I was quite surprised to find he had
described the rotation of the water column about its long axis when
a magnetic field was applied in that long axial direction, and a
central conductor on the long axis applied a radial electric current.

For some reason, I had associated the hydromagnetoelectrodynamic
effect with Einstein. Certainly, that was the means he had in mind for
pumping the coolant in a fridge he planned to replace the noxious, even
lethal ammonia-cycle machine in the domestic refrigerator unit.

Sincerely

Brian Whatcott
1045 East Pecan St
Altus OK 73521