- When an object moves far above the Earth's surface, calculating
its Gravitational Potential Energy becomes a bit more
difficult:
1 1 GPE(B) - GPE(A) = G*M(earth)*m(object) * ( ---- - ---- ) R(A) R(B)

whereG is the universal gravitational constant M(earth) is the mass of the Earth M(object) is the mass of the object R(A) is the distance of point A from center of Earth R(B) is the distance of point A from center of Earth

- One can use conservation of energy to calculate the speed an
object needs at the Earth's surface to reach an infinite
distance from the Earth. The
**escape velocity**for the Earth turns out to be[ 2*G*M(earth) ] escape velocity = sqrt [ ----------- ] [ R(earth) ]

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Copyright © Michael Richmond. This work is licensed under a Creative Commons License.