Re: Friction

["S.Goelzer" <sgoelzer@COEBROWNACADEMY.COM>]

Thanks!  I have never seen the source of this story.

I tell a version of this story every year, but I learned that the demons were called
'Grabitts' (perhaps more P.C.).
These were atomic sized bacteria - so we cannot get a microscope to see them.
I usually get way too far in a lecture on the frictional nature of grabitts with
students taking copious notes.  Then I draw models of them as pac-man with teeth
living in the rough surface.  On a good day some students begin to question my
veracity...

Scott

> Date:    Mon, 23 Oct 2000 14:05:59 -0400
> From:    "E. Leonard Jossem"
> Subject: Friction
>
> ITo those considering why a block sliding on a table top comes to a
> stop, I commend Eric Roger's "Demon Theory of Friction"
>
> The Demon Theory of Friction
> Eric Rogers
>
> How do you know that it is friction that brings a rolling ball to a
> stop and not demons? Suppose you answer this, while a neighbor,
> Fauystus, argues for demons. The discussion might run thus:
> You     I don't believe in demons.
> Faustus I do.
> You     Anyway, I don't see how demons can make frction.
> Faustus They just stand in front of things and push to stop them from moving.
> You     I can't see any demons even on the roughest table.
> Faustus They are too small, also transparent.
> You     But there is more friction on rough surfaces.
> Faustus  More demons.

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*****************************
S.Goelzer
Physics Teacher
Coe - Brown Northwood Academy
Northwood NH 03261
603-942-5531 ext43
sgoelzer@coebrownacademy.com
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