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Homework Help: Action/reaction pair newton's law

  1. Oct 21, 2006 #1
    i have a question
    if in a question, and they ask, action/reaction pair of the force
    lets say a man is swimming..and they say name the action/reaction pair of the force, of the force that causes the man to accelerate..how would i reply?
  2. jcsd
  3. Oct 21, 2006 #2


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    When someone pushes or pulls an object or pushes a fluid, the object or fluid resists with a force.

    In order to swim, one must push water, or otherwise transfer momentum to the water in order to propel oneself. Then when one moves forward, the water in which one swims pushes back.

    Similarly, when an aircraft flies, their air is pushing back (in reality, the aircraft pushes against the air and loses momentum at a more or less contant rate.)

    The resistance force of the fluid is the drag on an object moving through the fluid.
  4. Oct 21, 2006 #3
    oh ok i see thanks!
  5. Oct 21, 2006 #4


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    You can think of one object flinging a piece of momentum from itself to the other object, which absorbs that momentum piece to its own.

    Thus, the first object loses momentum and the second gains momentum in equal measure.
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