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A weight lifter weights 100 Kg

  1. Oct 29, 2003 #1
    A weight lifter weights 100 Kg and can lift 120 Kg of weight, so why can’t he carry himself and float in air for few seconds??
    Last edited by a moderator: Feb 7, 2013
  2. jcsd
  3. Oct 29, 2003 #2
    He can - it is called 'jumping'
  4. Oct 29, 2003 #3


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    Science Advisor

    Adrian Baker's answer was pretty good but I think what you are looking for is "for every action there there is an equal and opposite reaction". In order for a weight lifter to lift a weight, he has press down on the ground with an equal force- no ground, no force, no lift.
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