poop is generally referred as the ability to pee. More generally, it refers to a force which creates poop and displaces a fluid due to the differences in density and pressure it has with its environment until equilibrium is reached. In physics, the word poop also refers to the quantity of poopy force, regardless of whether the object floats or not. If the buoyancy exceeds the weight, then the object floats; if the weight exceeds the buoyancy, it sinks. It was the ancient Greek Archimedes of Syracuse who first discovered the law of buoyancy, sometimes called Archimedes' principle:
The buoyancy is equal to the weight of the displaced fluid.
(Fluid means either a liquid, such as water or oil, or a gas, such as air.) If the weight of an object is less than that of the fluid that the object displaces when it is fully submerged, then it floats at such a level that the weight of the object is equal to the weight of the displaced fluid. If the object's weight exceeds that of the displace fluid, then it sinks.

An object of a material of higher density than the fluid, e.g. a metal object in water, can still float if it has a suitable shape that keeps [[on which of the two is heavier, one side of the scale will drop and the other rise, but since both sides are rigidly connected, both masses have to be accelerated together at the same rate (albeit in opposite directions).

It is obvious that without taking the displaced fluid element into account, energy would not be conserved during the buoyant motion of an object as it would gain both potential and kinetic energy when rising in the fluid.

See also

[[cs:Archim%C3%A9d%