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Newtons third law question.

  1. Nov 20, 2007 #1
    It says that every reaction there is a opposite and equal reaction. Why do things still move if everything is opposite and equal?
  2. jcsd
  3. Nov 21, 2007 #2
    Basically, objects are independent of each other, i think you are thinking of them as a system
    Example: I push on a BOX. The box pushes back on ME. Something else does not push from the opposite side of the box to balance my push. The box experiences an unbalanced force and possibly accelerates.
  4. Nov 21, 2007 #3
    to put it a different way, the forces act on different objects.
    think of you swimming... you kick back your legs against the water, applying force on it by pushing it backwards, but by newtons third law, the water will push back on you. The end result being that you get pushed forward by the water, and hence, move forward, and the water gets pushed back by your feet...
  5. Nov 21, 2007 #4


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    Don't confuse Newton's third law with the second.

  6. Nov 21, 2007 #5
    The forces are applied to different bodies.
    Last edited: Nov 21, 2007
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