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Homework Help: Help with forces

  1. Sep 29, 2004 #1
    Help with forces!!!!!!!!

    I need help with this, I've been trying but I don't understand it. Can anyone help me????? :frown: :confused:

    A 830.0 kg car travelling on a level road at 27.0 m/s (60.5 mi/hr) can stop, locking its wheels, in a distance of 61.0 m (200.1 ft). Find the size of the horizontal force which the car applies on the road while stopping.

  2. jcsd
  3. Sep 29, 2004 #2


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    try [tex] W = \Delta K [/tex]
  4. Sep 29, 2004 #3
    I don't know how is exactly that formula, but I find one, maybe it's the same.


    [tex] a= (v^2-v_{i}^2)/(2* \Delta x) [/tex]

    Now I have other problem

    Find the stopping distance of that same car when it is traveling up a 19.9° slope, and it locks its wheels while traveling at 33.5 m/s (75.0 mi/hr). Assume that [tex] \mu_k [/tex] does not depend on the speed.
    Last edited: Sep 29, 2004
  5. Sep 30, 2004 #4
    please help me, this is urgent...
    Any formulas will be helpful
  6. Sep 30, 2004 #5


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    Dearly Missed

    1. What's the normal force exerted on the ground upon the car?
    2. How is the magnitude of frictional force related to the magnitude of the normal force?
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