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Homework Help: Free falling elevator

  1. Jan 12, 2012 #1
    In a free falling elevator, can you jump, my question is as simple as that, my teacher said you can't (due to newtowns 3rd law since there would be nothing with which I could cause the reaction of jumping) but still can you ?
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  3. Jan 12, 2012 #2


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    If the elevator is in free fall then you will probably be sort of "floating" as you aren't directly connected to it.
  4. Jan 12, 2012 #3


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    Hello vruls. Welcome to PF !

    If you are in the proper position you definitely could jump. If you jump very hard you would likely bang your head.

    If you jumped up you wouldn't come back down unless you collided with the ceiling and rebounded from it.
  5. Jan 12, 2012 #4
    Thanks, and hello to everyone else
    but why exactly would I be weightless? And what about inertia wouldn't that make me have weight?
  6. Jan 13, 2012 #5
    The elevator is falling with you so you can't tell whether you're falling or floating weightless.

    You still have mass and inertia. But it would look and feel like gravity had gone away.
  7. Jan 13, 2012 #6
    But I could still jump right?
  8. Jan 13, 2012 #7


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    you certainly could push off from the elevator floor (as sammy has said). Due to Newton's 3rd law, you cause a downward force on the elevator, which causes an upward force on you. But if you were in the middle of the elevator and weren't able to touch any of the sides, then you would be stuck (unable to jump), since you'd have nothing to push off from. (assuming the elevator isn't slowed down by air resistance).
  9. Jan 13, 2012 #8
    K thanks alot this was really usefull
  10. Jan 22, 2012 #9
    If you were on top of the elevator then you would have separated from it as you would weigh much less i think.
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