Buoyancy calculations determine whether an object will float or sink in a fluid, based on the principles of Archimedes' principle. This principle states that the upward buoyant force on an object submerged in a fluid is equal to the weight of the fluid displaced by the object. To perform buoyancy calculations, you need to know the object's volume and the density of the fluid. By comparing the object's weight to the weight of the displaced fluid, you can predict its behavior in the fluid. If the object's weight is less than the weight of the displaced fluid, it will float; otherwise, it will sink.