Posted by Kendall Raine on July 12, 2002 at 15:00:29:
In Reply to: Bzzzz.....Sorry. We have some lovely parting gifts for you at the door. posted by ed on July 12, 2002 at 13:39:56:
Ed;
Are you trying to determine the displacement of the weightbelt or the diver with gear?
The original question was not, "how much lift do I need to lift my weight belt in fresh versus salt water, it was how much weight can I take off my belt in fresh water if I'm neutral in salt water to start with?
Please go back and think about Archemedes Principle.
Yes, you adjust the weight belt, BUT, you adjust the weight belt by the relative weight per cubic foot required to float the WHOLE diver in one fluid versus another.
Your ball analysis is inapt inasmuch as you have changed the density of the object being floated. The question involves an object who's density does not change. They are different issues.