Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site brl-tgr.ARPA
Path: utzoo!linus!gatech!seismo!brl-tgr!gwyn
From: gwyn@brl-tgr.ARPA (Doug Gwyn )
Newsgroups: net.physics
Subject: Re: Monkey business
Message-ID: <3080@brl-tgr.ARPA>
Date: Sat, 9-Nov-85 19:43:42 EST
Article-I.D.: brl-tgr.3080
Posted: Sat Nov  9 19:43:42 1985
Date-Received: Mon, 11-Nov-85 08:05:34 EST
References: <2748@brl-tgr.ARPA>
Distribution: net
Organization: Ballistic Research Lab
Lines: 25

Having allowed sufficient time for readers to
ponder system instability, now I wish to observe
that there is a finite characteristic time for
the evolution of the instability (on the order
of sqrt(2*h/g), where h is the distance to the
pulley and g is as usual the gravitational
acceleration; more if the angular momentum of
the pulley is substantial), so if the monkey
climbs sufficiently fast he can be assured of
reaching the top before the counterweight does.

For sufficiently fast climbing rate, the
position of the counterweight at the end of
the monkey's climb is dependent on variables
such as rope density and moment of inertia of
the pulley.  If these are appreciable, the
counterweight will remain at its initial
position (except to the extent that the system
instability has procgressed).

If the monkey climbs much more slowly than the
characteristic time for system collapse, then
the experimental outcome is ill-determined.

The in-between behavior could be interesting..