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Homework Help: Vertical Circular Motion

  1. Jul 17, 2011 #1
    1. The problem statement, all variables and given/known data

    A 915kg car goes over a hill. If the radius of this curve is 43m, how fast must the car travel so that it exerts no force on the road at the crest.


    2. Relevant equations

    Fc = mv^2/r
    Fg = mg


    3. The attempt at a solution

    Fc = Fn+Fg
    Fn=Fg
    Fg=mg
    =(915)(9.81)
    =8976.15
    Fc=????
     
  2. jcsd
  3. Jul 17, 2011 #2

    Doc Al

    User Avatar

    Staff: Mentor

    OK.
    No. If there's no force on the road, what must Fn equal?
    OK.
     
  4. Jul 17, 2011 #3
    If the car must exert no force on the road at the crest, what does that say about the force the road must exert on the car at the crest? :)
     
  5. Jul 17, 2011 #4
    Should it be Fc = Fg - Fn ???

    but yes anyway, it will give same result.
     
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