vdoc

Chapter 11
E. Specialized Inspection Equipment
Part II.E.1
1. WEIGHTS, BALANCES, AND SCALES
Define and describe how to use these types
of tools. (Application)
Body of Knowledge II.E.1
Weight is a measure of how hard an object presses down on a scale, resulting from
the action of gravity. Weight and mass are two different quantities that are fundamentally
different. The weight of an object can provide an indication of the quantity
that we are actually measuring, mass.
Therefore, the weight of an object is determined by the mass of the object multiplied
by the gravitational acceleration.
Measuring Weight and Mass
SI units are used to measure physical quantities. The SI unit of mass is the kilogram,
which is also used in the everyday language of measuring weights. In the
United States, the pound can be either a unit of weight or a unit of mass.
Adopting Newton’s law (F = ma), we can convert between weight and mass. F
(or W) is the force due to gravity (weight), m is the mass of the object, and a (or g)
is the gravitational acceleration, approximately equal to 9.8 m/s² or 32.2 ft/s².
Balances and Scales
There are numerous types of balances and scales that are used to measure a
wide range of weights for different applications, such as laboratory, industrial,
research, and other applications. They offer different capacities, resolutions,
requirements, and configurations. Examples include:
• Lab balances
94