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Two football players are running at each other

  1. Apr 12, 2006 #1
    This may be a simple question but say if two football players are running at each other with equal momentum why does the one who gets lower so to speak win?
  2. jcsd
  3. Apr 12, 2006 #2


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    Because of their centers of gravity.

    If you're running, and you trip on a rock, you're going down. But if you're running and a floating rock at rest hits you in the chest. You're not going to fall down are you?
  4. Apr 14, 2006 #3
    Another aspect to consider in your scenario is that the ideal goal is to negatively influence the opponents "method of locomotion"
    In this case, it is his legs and feet.
  5. Apr 15, 2006 #4
    very simple. Your feet are the pivoting point.

    rotational moment (that is the tendency for your body to rotate forward or backwards) is given by :

    moment= force x perpendicular distance of line of force to pivot

    where the force in this case is your own weight.

    given this, if your centre of gravity is lower, and considering all else equal, your rotational moment is lower because the perpendicular distance of line of force to pivot is also lower ,so according to the equation above, it is harder to make you fall.
    Last edited: Apr 15, 2006
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