Physics: Principles and Problems

Chapter 7: Gravitation

Problem of the Week

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The radius of Saturn is 6.03 x 107 m. Therefore, 1.5 Saturn radii is 9 x 107 m. The diameter of 250 miles is about 4 x 105 m.

Radius is 2 x 105 m. Using the gravitational force equation, one can obtain forces for the near side and far side.

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  The tidal force is the difference between these two forces, which is about 0.05 N
 
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  Use the gravitational force equation to determine the weight of a 1 kg chunk of rock at the moon surface.
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  You can see that the tidal force pulling the moon apart nearly equals the gravitational force holding the moon together. Add a little spin to the moon and you have an unstable situation.
 
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