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Homework Help: Friction compared to applied force

  1. Nov 13, 2011 #1
    1. The problem statement, all variables and given/known data

    I am doing review questions about friction and am I little confused about the one I am currently doing. I have an idea of what the answer is but i want to be positive.

    The question asks to compare friction to applied force of an object on a horzontal surface. Compare them when the object is slowing down, travelling at a constant velocity and speeding up

    3. The attempt at a solution

    I have the answers as both will decrease, both will stay the same and both will increase but I feel like this may not be correct. Help would be appreciated.
     
  2. jcsd
  3. Nov 14, 2011 #2

    BruceW

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    Homework Helper

    Well the friction is usually modelled as a function of speed (either linear or as speed squared). So you are right about how friction will act in those situations.

    But the applied force is a bit more complicated. I think you'd need to write down a model of the friction force and the applied force and work it out. (In other words, I don't think there is a general answer)
     
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