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

However, this is good ONLY while on the surface of Earth. You become lighter as you rise from the surface of the Earth, but your mass (the amount of material you are made of) remains constant. Each kilogram of mass results in 2.2 pounds of force on Earth. Calculate your mass in kilograms (kg) from your Earth weight in pounds. ................
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