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Homework Help: Not sure how to get started on on prob

  1. Dec 13, 2003 #1
    A truck weighs 6000 lb. The truck is going around a curvewith a radius of 650 feet. The maximum friction force the road can exert on the tires is 1125 lb. it wants me to calculate the velocity in ft/sec

    I am sorta lost on this an y help would be great

    thanks
     
  2. jcsd
  3. Dec 13, 2003 #2
    Think about centripetal acceleration & centripetal force.

    What is needed to keep the truck moving along that curve, and what can the road provide?
     
  4. Dec 14, 2003 #3
    still having problems

    right now the only thing I know what to do is I converted the items that are in pounds to Kg. and feet to m

    struggling
     
  5. Dec 14, 2003 #4
    OK, centripetal acceleration is given by v^2/r.

    And by Newton's second law, we know that F=ma. Since the car is moving in a circular path, he is accelerating. The only force that is pointing towards the center of the circle is friction. So:
    F=ma
    Force of friction = m*(v^2/r)
    1125lb = 6000lb*(v^2/650ft)
    v=11.039701082909808568455053408699 ft/s
     
  6. Dec 14, 2003 #5
    x

    thanks alot i have been trying to catch up on all the homewok and study for my physics final

    thanks again
     
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