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berkeman
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#5
Dec27-12, 04:23 PM
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Quote Quote by genergy View Post
I did forget to put cubic meters. I don't think that there would be more energy but there might be less area to cause viscous drag as the object accelerated upwards.
One thing I've observed (as a scuba diver) is that if you inflate a baloon at depth and release it, it accelerates very slowly at first, and as it grows in size it accelerates faster. You are right that there is more drag as it gets bigger (and goes faster), but the added bouyant lift from the larger displaced water volume seems to overpower that.

Aside -- it is *very* disconcerting when you are in trouble and have to pull your Bouyancy Compensator (BC) vest's ripcord, to inflate it to take you to the surface -- if you are at any depth, you barely start to accelerate to the surface at all. As you rise, you go faster and faster, which is finally reassuring.