SM0486
Figure 2.
Weight Sets and their Case
j. The materials are listed in the order of their preference with regard to
stability.
The first four materials are also considered applicable for use in
smaller weights, in addition to materials such as gold (alloy), tantalum, and
aluminum. It is important to assume that the total error caused by changes in any
of the materials in the preceding list does not exceed one to ten parts per million
(ppm).
k. Mass Measurements. Since weight is the force with which a mass or body is
attracted to the center of the earth (the pull gravity), mass measurements
determine the force W (weight) produced in a gravitational field: W = (M) (G).
This force depends on gravity (G) which varies with latitude and altitude. Known
masses whose values are calibrated for specific locations are sometimes used. The
process by which an unknown weight (mass) is compared with a calibrated weight
(mass) is called a weighing.
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