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Question about the conservation of momentum?

  1. Jul 3, 2010 #1
    If I were to just spawn into a complete vacuum of space with no initial velocity (momentum). Disregarding the fact that I would die due to lack of pressure and oxygen, would I be able to move my arms or legs at all because I would have no place to take the momentum from?
  2. jcsd
  3. Jul 3, 2010 #2
    Weird question.
    If you spawned in space you must also spawn an awful lot of potential energy which defines what you are. Then what's the big deal that you then convert some of that potential energy to kinetic energy by flapping your arms? It's no different from what you do every day.
  4. Jul 3, 2010 #3


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    When you flap your arms your body will move in the opposite direction from the flapping - momentum will be conserved.
  5. Jul 4, 2010 #4
    But what if you don't flap them, what if you just move one arm over? What would happen?
  6. Jul 4, 2010 #5
    Then the rest of your body would move the opposite way such that your center of mass would remain the same.
  7. Jul 4, 2010 #6

    Then you could pull your head off and throw it away - that would conserve momentum too.
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