[Phys-L] Re: Buoyancy question

[hhaskell at MINDSPRING.COM (Hugh Haskell)]

At 19:30 -0500 12/9/04, Michael Edmiston wrote:
> Excuse the fact I am using mass in grams instead of force in newtons.
> My 15.6-gram object was floating, but could not possibly have displaced
> 15.6 grams of water because only 10 grams of water were present.
But when you were finished, you still had 10 grams of water in the
beaker, it was now occupying a total volume of 25.6 ml, because the
15.6 ml object was floating in it. Of course it displaced 15.6 ml of
water, and that 15.6 ml is not there--because it has been displaced.
If you had had 20 g of water in the beaker, the water level after
floating the object would have been at 35.6 ml. The amount of water
actually there is irrelevant until there isn't enough to get the
object off the bottom, but as soon as that minimum is reached any
more water added to the beaker is superfluous.

Hugh
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Hugh Haskell
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