Hi Alex,

Yes, you are correct, as is the example I gave. The force, or restraint, acting against the riders of the marry-go-round, that keeps the riders from flying off in a normal physics striaght line, is the screen around the marry-go-round's parameter. Although the screen isn't forcing the riders to the center of the merry-go-round, it represent the same force pushing the moon towards the center of the earth. However, because of the moon's speed, trend towards a straight line, and a force pushing the moon toward the center of the earth, the moon remain in orbit around the earth.

By the way, what is the force that is pushing the moon towards the center of the earth, or holding the moon in orbit if you will? I know it is called gravity, but what is gravity? This is the question. <vbg>

Also, is the force pushing the moon towards the earth's center or pulling the moon toward the earth's center.

Regards,

LelandJ