Originally posted by Aaron
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The mgh equation is just a shortcut for those not wanting to use the gravitational force equation and distance to calculate the work (or energy). The shortcut assumes a nominal radius of the planet and incorporates that and the planet's mass into a constant. So when using the shortcut, people often forget it is actually the attraction force between two objects with which they are dealing.
I agree. The small object does not store energy in itself because it was lifted. The force acting on the two objects was changed due to an increase in the distance between their centers. Work was done to increase that distance and so that energy was taken from the field. This actually decreases the energy stored in the gravitational field while the shortcut equation would indicate an increase in energy. The shortcut equation is just an approximation for small objects close to the surface of the earth.
At least the way I see things,
bi




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