Does a Pulled Air-Filled Rubber Ball Sink?

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A rubber ball filled with air will collapse under pressure when submerged, potentially losing buoyancy. It will only sink if the material becomes denser than water. The discussion also references how dolphins can dive efficiently by allowing their lungs to collapse, increasing their density and enabling them to sink. This principle of buoyancy and density is crucial for understanding underwater dynamics. Ultimately, the ability of an object to sink depends on its density relative to the surrounding water.
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If a rubber ball is fill with air, attached to a cord and pulled under water, I assumed it collapses under pressure at some rate. The question is, will it at some point lose enough bouyancy to sink to the bottom?
 
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If a rubber ball is fill with air, attached to a cord and pulled under water, I assumed it collapses under pressure at some rate.

yes


The question is, will it at some point lose enough bouyancy to sink to the bottom?

only if the material is denser than water...
 
Prolate steel spheroids, like the USS Thresher, will collapse when the water pressure exceeds its design pressure, and sink to the bottom. See

http://en.wikipedia.org/wiki/USS_Thresher_(SSN-593)

Bob S
 
Liquid carbon dioxide is more compressible than water, and undergoes a http://www.lbl.gov/Science-Articles/Archive/sea-carb-bish.html:
"At great depths, CO2 is denser than sea water, and it may be possible to store it on the bottom as liquid or deposits of icy hydrates," Bishop explains. "At depths easy to reach with pipes, CO2 is buoyant; it has to be diluted and dispersed so it will dissolve."
 
I heard once that dolphins use this to be able to efficiently dive deep. They go deep enough that their lungs collapse sufficiently that they become negatively buoyant and can just drop down to their desired depth.
 
DaleSpam said:
I heard once that dolphins use this to be able to efficiently dive deep. They go deep enough that their lungs collapse sufficiently that they become negatively buoyant and can just drop down to their desired depth.

Just to clarify and make sure I understand, upon having their lungs collapse, the reason they are able to sink lower is because they are more dense than the water under them.

Am I right?
 
Yes, although I just vaguely remember reading that in a pop-sci journal so it is not a reliable reference or anything.
 
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