Re: [Phys-l] buoyancy on a submerged pole

[John Mallinckrodt <ajm@csupomona.edu>]

I continue to be utterly mystified by all the wrangling about this "problem" and the many attempts to resolve it experimentally.   I understand very well that "physics is an experimental science" and all that, but it would appear that some of us think Newton's laws might actually not apply to this exceedingly simple macroscopic system.

Can somebody explain to me what I'm missing?

John Mallinckrodt
Cal Poly Pomona

I wrote:

> Chuck Britton wrote:
>
> > My hypothesis (which I am QUITE ready to have disproved - 
> > experimentally) is that SuperGlue or threads will exert the SAME 
> > upward force on the bottom sheet of glass.
>
> It seems to me that you are hypothesizing a situation where the BOX is subject to only the following three forces
>
> 1. A gravitational force (DOWNWARD)
>
> 2. A net force due to the fluid that presses on the sides and the top of the box (DOWNWARD)
>
> 3. A force due to the glue that attaches the box to the aquarium bottom and excludes water from underneath the box (DOWNWARD)
>
> yet somehow manages NOT to accelerate downward.
>
> Have I misunderstood the hypothesis?  Are you imagining some other force that is acting on the box?  If so, what is it?