From: Chuck Britton [mailto:cvbritton@embarqmail.com]
To: phys-l@carnot.physics.buffalo.edu
Sent: Fri, 05 Nov 2010 15:22:28 -0400
Subject: [Phys-l] A Crude Attempt at Analysis
Assume a cubical volume of water. If we integrate the net force over
the entire surface of that cube, we come up with a total force that
is the weight of the fluid in that cubical volume.
ok so far? (I think I saw this a physics text - so it MUST be right.)
Let's position that cubical, mathematical volume directly ojn the
glass at the bottom of my aquarium, positioned exACTLY such that
there is not one single molecule of water below this mathematical
volume.
It seems to me (naively) that we better come up with exACTLY the same
total force when we integrate force around all SIX sides of this
mathematical volume as we did the first time.
That only follows if the behavior of the cube is the same as before - that it floats or sinks or stays with the same accel. as before. If it stays on the bottom now instead of accelerating upward, then I don't agree.
jg
The pseudoContact force of the bottom is supplying exACTLY the same
contribution to the total force as did the layer of water that used
to be there.
Go ahead - shoot me down.
I ain't no theoretician and I CAN take a hit when it's called for.
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