The principle behind the law of buoyancy, also known as Archimedes’ principle, states that an object submerged in a fluid experiences an upward force equal to the weight of the fluid displaced by the object. This principle helps explain why objects float or sink in liquids. If the upward buoyant force is greater than the weight of the object, it will float; if it’s less, the object will sink. This law applies to all fluids, including liquids and gases.