Question about the conservation of momentum?

AI Thread Summary
In a vacuum, even without initial velocity, a person can still move their arms or legs by converting potential energy into kinetic energy. Flapping arms results in movement in the opposite direction, demonstrating the conservation of momentum. If only one arm is moved, the rest of the body will shift in the opposite direction to maintain the center of mass. The discussion humorously suggests that even extreme actions, like throwing one's head, would also conserve momentum. Overall, movement in space is governed by the same principles of physics as on Earth.
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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?
 
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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.
 
When you flap your arms your body will move in the opposite direction from the flapping - momentum will be conserved.
 
mathman said:
When you flap your arms your body will move in the opposite direction from the flapping - momentum will be conserved.

But what if you don't flap them, what if you just move one arm over? What would happen?
 
Then the rest of your body would move the opposite way such that your center of mass would remain the same.
 
:smile:

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