Would a rigid object thats slightly negative buoyant sink all the way to the bottom of a 10,000 ft fresh water lake?

I'm going to make a few questions regarding the topic involving a submarine & of a cartesian diver to help better understand buoyancy.

  • $\begingroup$ The deepest lake on Earth is less than 6000 feet deep. $\endgroup$ – akhmeteli Oct 6 at 20:57
  • $\begingroup$ haha this was hypothetical but thank you @akhmeteli! $\endgroup$ – Rip Oct 6 at 21:07

No. If the object has a compressibility much less than water (nothing is perfectly incompressible) it would only sink part way. At a depth of 10,000 ft, the water would be about 1.4% denser, assuming temperature remained constant.

  • $\begingroup$ Well I'm a little confused because I had someone else say otherwise. May I ask If I hypothetically had an indestructible closed container full of water that was negative buoyant would this still eventually stop sinking at a certain depth due to the water becoming denser the deeper it sinks? $\endgroup$ – Rip Oct 6 at 20:20
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    $\begingroup$ If by indestructible you mean incompressible, it would still reach a neutral depth (assuming it starts out only slightly negative). But if it’s a soft indestructible container, that allows the water inside to be compressed as the external pressure increased, then it would sink to the bottom. $\endgroup$ – Ben51 Oct 6 at 20:23
  • $\begingroup$ That makes total sense to me so I thank you. I must ask though if you say water actually is compressible then why do many say that its incompressible? $\endgroup$ – Rip Oct 6 at 20:30
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    $\begingroup$ It is very much less compressible than air, say, so for many aerodynamic flows where compressibility is important it can safely be neglected in the hydrodynamic case. $\endgroup$ – Ben51 Oct 6 at 20:34

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