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Centripetal force problem

  1. Jun 8, 2014 #1
    1. The problem statement, all variables and given/known data
    A car of mass 2000 kg rounds a circular turn of radius 20 m. If the road is flat and the coefficient of friction is 0.7 between the tires and road, how fast can the car go without skidding?

    2. Relevant equations
    Fc = m(v2/r)

    3. The attempt at a solution
    I tried to find the centripetal force by doing
    2000(9.8) = 19600
    19600(.7) = 13720
    then I plugged that into the above equation to find the velocity
    13720 = 2000v2/202
    5488000/2000 = v2
    2744 = v2
    [itex]\sqrt{}2744[/itex] = v
    v= 52.38 m/s. The correct answer is 11.7 m/s
  2. jcsd
  3. Jun 8, 2014 #2


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    Homework Helper

    Why did you square the radius?

    Other than that you are correct.
  4. Jun 8, 2014 #3
    That was my mistake. Thanks!
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