Recommendations by Subject Headings—Recommended …

That is, mass and weight have the same values (kgm = kgf or lbm = lbf), but they are different since one is a mass and the other is a force and two different approaches to a given system of units are being used (absolute/gravitational). Combining the absolute/gravitational SI or inch-pound systems of units can lead to confusion in many ... ................
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