A jar filled partially with water has an object floating in it. The jar is open. Now, if the jar is closed and a vacuum pump is used to pump the air out, what will happen to the floating object? will it rise up more or sink or ...? and why?

The vacuum pump will get the air out and lower the pressure in the jar.  The water will start boiling, and the vacuum pump will also get that damp out.  All this until the energy level of the water is low enough to have the temperature below the freezing temperature of watre and you will have frozen boiling water.

Now what is the influence on the floating object? It will sink and then freezes in the boiling ice.

Posted by Hugo on 2005-07-22 19:00:10