100
A two ounce, solid steel marble is place in a bathtub full of water. The marble sinks to the bottom. An empty, two pound steel bowl is placed in the bathtub and it floats. Why?
The air inside the bowl makes it more buoyant than the steel ball. The density of the bathtub water is greater than that of the empty bowl, so the bowl floats. The water's density is less than that of the solid marble, so the marble sinks.