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Newtons 3rd law

  1. Mar 7, 2007 #1
    Newtons third law states that for every force there is an equal an opposite force. This doesn't mean that these forces are balanced though? Things like cars or people walking can still accelerate so these forces can't be balanced?
  2. jcsd
  3. Mar 7, 2007 #2
    When you walk you push down on the ground and it moves you forwards.

    At the same time, the earth pushes back on you and moves backwards.

    Equal and opposite.
  4. Mar 7, 2007 #3
    Since they are equal and opposite though, would that imply that they are balanced forces?
  5. Mar 7, 2007 #4


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    The proper statement of Newton's third law is:

    If body A exerts a force on body B, then body B exerts a force on body A that is equal in magnitude and opposite in direction to the force exerted by body A.

    By definition, they are equivalent. Newton's 2nd law deals with accelerations due to a net force.
  6. Mar 7, 2007 #5
    The answer is no because the two forces act on different bodies.
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