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# Re: Vector Rules

From: Gravity is falling in a good way today <KOCHTE@s...>
Date: Tue, 07 Oct 1997 16:34:45 -0500 (EST)
Subject: Re: Vector Rules
``````
>@:) You seem to be forgetting that there is a major difference between
>@:) trying to rotate an object in space Vs rotating it in water
>@:) fighting the resistance of the liquid.  You should be able to
>@:) maneuver the big ships quite quickly
Status: RO

>
>  This mailing list reminds me of a Dilbert poster in my manager's
>office: "The Boss Zone, where time and logic no longer apply!"
>Except it would be physics and logic.

*grin*

>  Anyway, yes water causes drag but the fact is that massive things
>are hard to move anywhere, in space, in water, in air, wherever - if
>they have mass they have inertia and they're hard to move.  The more
>massive they get, the harder it is to move them.

How 'bout a better example!  ;-)

Let's take, say, a 1 metric ton beam of steel, and a 1 lb shaft of wood.
Set them on a pivot point in such a manner that they will not fall off
(we assume they won't for sake of arguement ;). As in the following
illustration:

============================
|			     |		   -----------
============================ 		^
^			       / \
/ \			      /   \
/   \			      |   |
|   |			      |   |
-------			     -------

Assume in this system that air friction is negligible, and that the
friction
between the pivots and the beam/shaft is negligible (there's really
really
good oil on there). Now try and rotate them (and stopping them after
they've
gone a half turn). Just go up there and give that ol' steel beam a good
push!
Impart the *same* push/force to the shaft of wood.

Better, give the shaft of wood a push to move it, then give the *same*
push
to the steel beam. Okay, now push harder.  ;-)

You can practice this in real life (kids! do this at home! WITHOUT
parental
consent - but I take no claims for any messes you make in the mean
time!)
Get a 10' section of PVC pipe, fill it with a material of your choice
(dirt,
water, whatnot), cap both ends. That'll represent the steel beam above.
Get
a straw. That'll represent the shaft of wood. :)  Put both on a 'lazy
susan'.
Now...try and rotate them. No, really. This will work, and *ought* to
demon-
strate the basic principles trying to be shown above.

Mk
------------------------------------------------------------------------
-
During the run-and-fight-and-run-again battle through this forest of
horror,
she is finally cornered. Her weapons have been left deep in the bodies
of the
slain or broken against the granite-hard scales of these snakes that are
not
snakes. Her stand to the death must be fought here. Though her only
weapons
are her hands and her deep and wide knowledge of the slayers, she does
not
fear them. They will die. Of this she is sure.
``````

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