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wrote:
otnmbrd wrote:

wrote in message
groups.com...

Maybe I've killed too many brain cells over the years or just

forgotten

some basic stuff but my understanding of Archimedes Principle is

that

the buoyant force on an object is equal to the weight of the fluid

it

displaces. This means that my boat that weighs 8000 lbs must

displace

8000 lbs of water in order to float. If she takes on 8000 lbs of
water, she sinks cuz the buoyant force doesnt balance the weight.
Right?
So, why do people make a distinction 'tween displacement and

weight?

This may not be what you are looking for, but......
There are a number of weights and tonnages associated with

boats/ships, that

need to be differentiated.
For instance:
Displacement
Deadweight
Lt. Ship
Gross tonnage
Net Tonnage
Etc.
So .... each of these "weights" (and not all are) refer to different,

specific weights/measurements associated with the boat

otn

Hmmm...."Displaces more water than its weight..." According to
Archimedes Princ. thsi means that there is a net upward force on the
boat instead of a balance. With a net upward force, she would rise out
of the water so I am not sure this is possible. I may be wrong, its
been many years since I thought about this.

An 8000lb boat will displace exactly 8000lb of water. Basic F=MA, where
A=acceleration due to gravity. The important point is that where the
*volume* of the 8000lb of boat is greater than that of 8000lb of water
(i.e. lower density), the boat floats. Density greater than
water...glug, glug, glug...

Keith Hughes