3. Air buoyancy correction

Archimedes' principle makes it possible to determine the density of an object that is as irregular in shape as it is in volume, and which cannot be obtained by direct measurement.

If the object is weighed first in air and then in water, the difference in weight will be equivalent to the weight of the volume of water displaced, which is the same as the volume of the object. In this way, the density of the object's weight (weight divided by volume) can easily be determined.

In high-precision weighing, for each weighing operation in air and water, the weight displaced in air and water must be taken into account to obtain the correct density and volume.

To determine the influence of air buoyancy on the calibration result of a mass, it is essential to know the density of the fluid (ambient air) and the density of the...