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0 pointsdatameta2y ago0 comments

Buoyancy is indeed not affected by gravity, you're correct.

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4 comments · 3 top-level

antod2y ago· 1 in thread

Depends how compressible the fluid you're floating in is right? Note that's 'fluid' rather than just liquid.

As you increase gravity, with fully compressible fluids the buoyancy scales the same as weight, you wouldn't sink lower. But with any incompressibilty you'd need to displace proportionally more (ie sink down more) to counter the increasing weight.

(I think)

Intralexical2y ago

> But with any incompressibilty you'd need to displace proportionally more (ie sink down more) to counter the increasing weight.

The water would also weigh more. Buoyancy is the force of the water around the volume you displaced being pulled down into that space, exerting pressure that pushes you up. So you'd float just as well.

Actually, the compressible fluids would become denser, and make it easier for you to float (assuming you're relatively incompressible). At the extreme end, you could swim in pressure-liquified air (assuming you survive being crushed, of course).

bugbuddy2y ago

This is technically wrong. Increase in gravity does affect buoyancy because air density changes with gravity. The reason is that the column of air above you is compressed by gravity. With very large gravity, all the atmosphere could be compressed down to possibly a few km.

datametaOP2y ago

Replies are accurate (more precise?), it is more true to say that buoyancy in a virtually incompressible liquid is not affected by gravity because even if gravity is increased, the water experiences it the same as the buoyant mass.

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