Buoyancy is the upward force exerted by a fluid (liquid or gas) on an object that is partly or fully submerged in it. This force opposes the object's weight and is caused by the difference in pressure exerted on the object's bottom compared to its top, due to fluid pressure increasing with depth. The magnitude of this buoyant force equals the weight of the fluid displaced by the object. If the buoyancy is greater than the object's weight, the object floats; if less, it sinks; if equal, the object remains suspended or neutrally buoyant.
