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?
(In reply to I think...
Agree that this is a problem of buoyancy.
Assumig that there is no air trapped in the floating object nor it has any air vent, there will not be any cange in the ass of the floating object. For a floating object the upthrust exerted by the fluid is equal to the weight of the object, which has not changed.
There will be no change when the air above the fluid is sucked out, that is the floating object will neither sink more down or come up................................(Vinod)