AVR-Chat

I might be wrong but what you are saying is if I have a non-compressable ball weighing 10 oz displacing 1 cubic foot of water it would take the same amount of force to hold it under 50 foot of water as it would at 100 feet? If weight and volume didnt change what would keep it from going deeper? I think I might be missing something.

Brian

--- In AVR-Chat@yahoogroups.com, "Graham Davies" <Yahoo37849@...> wrote:
>
> --- In AVR-Chat@yahoogroups.com, "Brian" <blue_eagle74@> wrote:
> >
> > From what I know, as the water
> > level rises the pressure at the
> > bottom increases causing more
> > of an uplift of an object held
> > at the bottom.
> 
> OK, forget Archimedes, have a word with your tenth-grade physics teacher.
> 
> Bouyancy has nothing to do with pressure.  The upward force on an object imersed in a liquid is the weight of the liquid displaced minus the object's weight.  To a first approximation, this is constant with depth of imersion, which is why your idea is a bad one.
> 
> Arguing about second order effects is fine, but it's still a bad idea to use second order effects to make a measurement when sensors are available for the first order effect itself (pressure).  As others have posted, there will be a very small variation of the force of bouyancy depending on the relative compressibility of the liquid and the object.
> 
> Graham.
>