Newton's 1st Law; the Law of Inertia: - NASA

STUDENT WORKSHEET: Conversion . . . Weight. Units of mass: Metric (SI) = kilograms (abbreviated as "kg"); English = slugs. Notes: Slugs are not often used in measurements anymore. On Earth we can convert kilograms directly into pounds (of force) by a simple multiplicative constant. However, this is good ONLY while on the surface of Earth. ................
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