ABSTRACT
The only internationally recognized system of units is the System International, with the base units mass = kilogram, length = meter, and time = second. The specialist in flow measurement, and engineers in general, should be familiar with the relations between these three systems of units as they apply to various quantities such as force, weight, and pressure. In the English Engineering system, however, the unit of force is the pound-force, the unit of mass is the pound, the unit of length is the foot and the unit of time is the second. The subscripts on “lb” are a consequence of the choice of the term “pound” for both the force unit and the mass unit. Weighing is the process by which the mass of an object is determined by the gravitational force on it, corrected for the buoyant force exerted on the object by the medium in which the object is weighed.
