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Doc Al
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#2
Dec11-12, 09:15 PM
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Where you are going wrong is with your equation for Gravitational Potential Energy:
Quote Quote by bobbles22 View Post
Gravitational Potential Energy = Eg = (GMm)/r
You left out the all-important minus sign in front:
GPE = -(GMm)/r
However, as it gets closer, the force from the Earth increased, as the separation 'r' off the objects decreases, the gravitational potential energy increases.
Using the correct expression, you'll see that the GPE decreases (becomes more negative) as objects approach and r decreases.

See: Gravitational Potential Energy