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I remember my teacher saying that anti-lock brakes worked better

  1. Oct 31, 2011 #1
    I remember my teacher saying that anti-lock brakes worked better because of the static friction coeffiecient was higher than the kinetic friction, but i never understood why. Is it beacuse when you stab the brakes their is a larger impulse?
  2. jcsd
  3. Oct 31, 2011 #2


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    Staff: Mentor

    Re: Friction

    The static friction coefficient between the wheels and the ground is higher than the kinetic friction coefficient. It doesn't have anything to do with how hard you push on the pedals - it is typical of most static and kinetic friction situations.
  4. Oct 31, 2011 #3
    Re: Friction

    carry out a simple experiment:
    take an object ,keep it on a flat surface. Now start tilting the table SLOWLY. not down the angle with horizontal the surface makes at which the object just starts sliding. the this is alpha.
    Now take a vibrating surface which continuously vibrates with a small amplitude. The vibration shall be in the horizontal direction and sufficiently rapid. Keep the object on it. tilt the surface. Note the angle again, say, beta.
    compare alpha and beta.
    you will find that alpha>beta. Why?
    this is because coeff. of friction in static condition is more than than in dynamic condition.
  5. Nov 1, 2011 #4
    Re: Friction

    thanks for the responses guys, so when I raise the plane and its vibrating the object will slide sooner.
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