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Picking yourself up

  1. May 26, 2004 #1
    how come if u sit down on a chair, you cant pick ur self up with your hands
    like say u sit on a chair and u cross ur legs with nothing touching the ground or floor, and taking ur hands and tryin to lift the chair with u on it...
    how come you cant do that
  2. jcsd
  3. May 26, 2004 #2


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    Because if you apply an upwards force on the chair, it applies an equal force downwards on you (on your hands, but you're considered a rigid body in this case, so it's downwards on you as a whole). Normally, if you were not on top of the chair (if you were on the ground) then you would end up transferring this force downwards onto the ground. However, since you're on the chair, you transfer it downwards to the chair. The force that you apply upwards on the chair is ultimately counterbalanced by the force that you end up applying downwards on the chair, resulting, of course, in no lifting of the chair.
  4. May 27, 2004 #3
    I'll tell you one thing, that would look damn funny :biggrin:
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