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Homework Help: What is Satellite Motion?

  1. Dec 15, 2008 #1
    1. What is Satellite Motion?

    2. What are the main concepts of Satellite Motion?

    I googled these for 6 hours yesterday and never came up with any solid answers. I have also checked the school library and have found no solid answers either. All that I get is a bunch of experiments that newton did about Satellite Motion but not a definition.
  2. jcsd
  3. Dec 15, 2008 #2


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    Not sure it's specifically for satelites but for any object in orbit - the centrifugal force outward balances the gravitiational force inward.
    This sets a fixed speed for any orbit radius.
  4. Dec 15, 2008 #3

    D H

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    That is only true for circular orbits, and which circular orbits never occur in nature -- or artificially. That said, except for Mercury and Pluto, the planets are in nearly circular orbits.

    One key main concept of satellite motion is that gravity is by far the dominant force on a satellite. The same is true for an arrow. An arrow and a satellite differ in that the arrow falls for a short time before it hits the ground. A satellite falls for a long, long time before hitting the ground. Satellites with perigee above 16,000 km or so will essentially fall forever.

    Ignoring perturbations, another key concept of satellite motion is that they follow a conic section.
  5. Dec 15, 2008 #4


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    I think you mean elliptical orbits which are predicted by Kepler's first law.
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