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Homework Help: Friction is giving me trouble

  1. Oct 7, 2004 #1
    This problem is giving me trouble. The x-component is -12i, but I don't know how to find the y-component. Can anyone tell me what the forces acting on the block are?

    A 12 N horizontal force F pushes a block weighing 6.0 N against a vertical wall (Figure 6-25). The coefficient of static friction between the wall and the block is 0.65, and the coefficient of kinetic friction is 0.45. Assume that the block is not moving initially.


    (b) In unit-vector notation, what is the force exerted on the block by the wall?
  2. jcsd
  3. Oct 7, 2004 #2
    Well, if this were a block in a horizontal plane how would you indicate the force of friction relative to motion? Also if this were a block just sitting on a horizontal plane what forces would be acting and in which directions?
  4. Oct 7, 2004 #3
    To be honest, I don't know. I can barely understand my professor because of his accent, and my book is useless because it is written in a very complex manner with examples that don't have anything to do with the problems given. I have no idea how to do over half of the problems on the homework assignment and I am dreading the next exam.
  5. Oct 7, 2004 #4


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    Ask yourself, does the block has mass? Yes so there's weight force, The wall is being pushed against has friction with the block?? yes, so the there's friction pointing against movement. Those are your forces on the y-axis.

    Now you found what were the forces on the x-axis because the force applied to the block is horizontal. Consider for the Wall force a vector in its components.
    Last edited: Oct 7, 2004
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