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Homework Help: Accleration and force?

  1. Oct 2, 2011 #1
    An athlete (mass of 50 kg) is moving with a constant velocity of 5ms. Determine the resultant force acting on him.

    If it's a constant velocity he is not acclerating? Therefore a = 0 m/s/s; F=ma F=50 X 0 = 0N?

    But there has to be a force dosent there? Would the force be equal to the mass affcted by gravity f=mg = 50 490.5N or is it 0N?
     
  2. jcsd
  3. Oct 2, 2011 #2

    cepheid

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    Why?
     
  4. Oct 2, 2011 #3
    So if he's moving at a constant velocity --- hes not accerating therefore threre is no force affecting his velocity?
     
  5. Oct 3, 2011 #4

    cepheid

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    No NET force, yes. Meaning all the forces that are acting on him (if any) must cancel each other out. That's Newton's second law. No net force means no acceleration.
     
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