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Miia
Oct 18, 2007, 08:02 PM
If the moon was sitting on the surface of the Earth, what force would be holding the two planets together.. I was told that the distance between is not zero... and to draw a diagram.. Help please

bignaked101
Oct 18, 2007, 08:28 PM
If the moon was on the surface of the earth, the force holding them together would be gravitational force, the reason for this would be because the earth pulls us down, and so does the moon.

Here is a diagram:

http://img.photobucket.com/albums/v672/cokefan111/G-Force.jpg

Capuchin
Oct 18, 2007, 11:51 PM
If the moon was on the surface of the earth, the force holding them together would be gravitational force, the reason for this would be because the earth pulls us down, and so does the moon.

This diagram isn't very clear. Why is all the gravity pointing in the same direction? The moon is pulling the Earth towards it.

ebaines
Oct 19, 2007, 05:58 AM
Hello Miia. Whenever you do any calculations regarding gravity, you measure distances between objects using each object's center of gravity, which for a round object like the earth or moon is at its center. Thus if the moon was sitting on the surface of the earth the distance you use is the sum of the earth's radius plus the moon's radius.