An object will float on top of a liquid if its density is...

An object will float on top of a liquid if its density is less than that of the liquid. This principle is based on the concept of buoyancy, which is described by Archimedes' principle. According to this principle, when an object is placed in a fluid, it experiences an upward buoyant force equal to the weight of the fluid that it displaces.

If the density of an object is lower than the density of the liquid, the weight of the fluid displaced will be greater than the weight of the object itself, allowing the object to float. Conversely, if an object is denser than the liquid, it will sink because it cannot displace enough liquid to generate a buoyant force that equals its weight. When the densities are equal, the object would remain suspended in the liquid rather than floating on top. Therefore, the relationship between the densities of an object and the liquid directly determines whether the object will float or sink.