Is gravity a theory or a law?

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• Well, that's an exaggeration. The Moon is moving away from the Earth at about 2cm per year, so in 10,000 years, it will be 20,000cm farther away... or 200m.
  
  The Moon's gravity is not changing to a degree which would cause this. What's happening, according to the theory, is that the Earth's spin, along with its tidal buldge is adding some energy to the Moon causing its orbit to slowly increase.

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  by yeroco on December 22nd, 2008

• Gravity is a pretty weak interactive force. In this case, gravity is still present, but it has been overcome. As you are aware when something spins around a center point, it tries to move away from the point...I know you are probably only a third grader, but there is still an example that might help you...think of a tetherball. When you hit it on the playground, and it goes around the pole, does the tether go slack as the ball floats around the pole, or does the string go tight as the ball tries to pull away? This is called centrifugal force, and you will learn about it next year, in 4th grade.

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  by TheicidalManiac on April 3rd, 2011

• No. Circular motion results in centripetal force, not centrifugal. The force is towards the center of the circle, not the opposite. Please, learn some physics before you lecture it.

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  by Considerable on April 4th, 2011

• Look who's talking, Considerable. Centrifugal force IS at play here. It was not only readily apparent to me, but before I put it down on this forum I checked with a dozen or so astronomy and physics forums. Indeed , the rotating masses do result in a centripetal force, but there is an outward pressure that is caused by tidal acceleration, is there not? It is my understanding that you simply have a scenario here wherein centripetal force is being overcome by the centrifugal.

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  by TheicidalManiac on April 6th, 2011