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Homework Help: Centripetal acceleration question: Please help.

  1. Mar 31, 2007 #1
    1. The problem statement, all variables and given/known data
    A 13500 N car traveling at 50.0 km/h rounds a curve of radius 2.00x10^2 m. Find the following:
    a). The centripetal acceleration of the car.
    b). The force that maintains centripetal acceleration
    c). the minmum coefficient of static friction between the tires and the road that will allow the car to round the curve safely.

    2. Relevant equations
    a). ac=vt^2/r
    b) i think i would use: Fc=mvt^2/r but I am unsure.
    c) i do not know this equation.

    3. The attempt at a solution
    For a). I have: 14^2/200=0.965
    for b). I know the answer is 1.33x10^3 but Im still having difficulties trying to solve this.
    for c) I know the answer is 0.0985 but I still have to figure out b). first. Please help me, any help is greatly appreciated. Thanks.
  2. jcsd
  3. Mar 31, 2007 #2
    a) is correct
    does the 13500 N car refer to its mass?
  4. Mar 31, 2007 #3
    I think so...the question just states "a 13500 N car..." so I was thinking that F=ma so mass=13500/.965=13989.6. But I'm not for sure.
  5. Mar 31, 2007 #4


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    13500 N is the weight of the car, in other words the gravitational force on it. To find the mass of the car, divide the weight by the acceleration of gravity, mass= 13500N/9.80m/s^2

    Then multiply this mass by v^2 to find the centripetal acceleration
  6. Mar 31, 2007 #5
    So the mass came out to be...1376.15 kg. Then I used the Fc=mv^2/r equation and got: 1348.63.
    Then I use the equation Fc=mus*Fn. 1.34x10^3/9.8*1376.15=.0985.
    Last edited: Mar 31, 2007
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