Re: Pendulum mechanics

Michael Lorrey (retroman@tpk.net)
Fri, 18 Jul 1997 22:26:57 -0400


Damien Broderick wrote:
>
> At 08:13 PM 7/17/97 -0400, Mike Lorrey of spacedrive fame wrote:
>
> >How can a little kid (or an adult for that matter) sit on a perfectly
> >still playground swing, begin rocking back and forth, and within a
> >minute be wizzing back and forth to a pretty good height, without ever
> >touching the ground or other still grounded object?
>
> Michael, Michael! It's connected at the top. (Unlike the spaceship.)
>

That doesn't mean anything. As a pivot point it is merely a fulcrum if
reaction mass is expended, according to Newton's Third Law. Since the
rider on the swing is at a standstill, and has no way to push against
anything, how do they develop the significant levels of momentum they
do?

-- 
TANSTAAFL!!!
			Michael Lorrey
------------------------------------------------------------
mailto:retroman@tpk.net		Inventor of the Lorrey Drive
Agent Lorrey@ThePentagon.com
Silo_1013@ThePentagon.com	http://www.tpk.net/~retroman/

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