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is (F=mg) equal to (F=GmM/r^2)? And what's the difference between them?

Qmechanic
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Zheer
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1 Answers1

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The Newton law of universal Gravitation is given by $$ F = G \frac{m M}{r^2} $$ For two bodies of mass $M$ and $m$. When describing gravitational effects near the surface of the earth, its common to use the approximate formula $F = m g$, where $g = G M/R^2$, with $R$ being the earth´s radius and $M$ the earth mass.

Alejandro Celis
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