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Question about Newton's 3rd law nd motion

  1. Jan 4, 2015 #1
    Now let's say I push a box. The box will accelerate (before stopping due to friction). But when I push the box the box 'pushes' me too. I heard that acceleration occurs only when there is a force imbalance. But if the two forces are equal, then how could this cause an acceleration?
    Please explain easily as I am inexperienced in this matter.
  2. jcsd
  3. Jan 4, 2015 #2


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    The two forces are equal and opposite:true.
    But there is only one force on the box, due to your push.
    The third law (reaction) is not the same as the first law (equilibrium / non equilibrium).
  4. Jan 4, 2015 #3


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