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Homework Help: What is the minimum stopping distance

  1. Oct 2, 2005 #1
    I have gotten stuck on this problem because I cant figure out the formula to solve it so really all i need is the formula. Ive read the book but i have this class online and have no instructor...please help if you can.
    Heres the Problem:
    A load of steel with a mass of 6000 kg rests on a flatbed of a truck. It is held in place by metal brackets that can exert a maximum horizontal force of 8000 N. When the truck is traveling 20 m/s, what is the minimum stopping distance if the load is not to slide foreward into the cab?
  2. jcsd
  3. Oct 2, 2005 #2


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    F = ma.

    Here's a start. You know the F is 8000N. You know that the weight of the load from gravity (which has a=32 ft/sec sec) is 6000N. So what is the acceleration that results from a force of 8000N?

  4. Oct 2, 2005 #3
  5. Oct 3, 2005 #4
    You'll find that it works really well to draw out a diagram on this one. Remember that the block is also traveling at 20 m/s.
  6. Oct 3, 2005 #5
    Ok i think i figured it out but i am getting two different answers when i do the problem...i got 150 m and 156 m can someone tell me if i might be close to the answer?
  7. Oct 3, 2005 #6
    You have the mass of the load already so you can find the maximum acceleration

    Find the maximum acceleration you can have without the straps breaking. Then calculate the stopping distance using your kinematics equations.

    I get 150 m as an answer
    Last edited: Oct 3, 2005
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