Displacement (fluid)

Thus, buoyancy is expressed through Archimedes' principle, which states that the weight of the object is reduced by its volume multiplied by the density of the fluid.

The amount of fluid displaced is directly related (via Archimedes' principle) to its volume.

In the third case, the object is suspended under the surface of the liquid and the increase of weight of the vessel is measured.

The mass of the displaced fluid can be expressed in terms of the density and its volume, m = ρV.

The weight of an object or substance can be measured by floating a sufficiently buoyant receptacle in the cylinder and noting the water level.

Measurement of volume by displacement, (a) before and (b) after an object has been submerged. The amount by which the liquid rises in the cylinder (∆V) is equal to the volume of the object.