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Homework Help: Normal forces -

  1. Sep 24, 2007 #1
    1. The problem statement, all variables and given/known data
    A 23-kg suitcase is being pulled with constant speed by a handle that is at an angle of 25 degrees above the horizontal. If the normal force exerted on the suitcase is 180N, what is the force applied to the handle?

    2. Relevant equations
    net force =ma[tex]\vec{}[/tex]
    Voy = Vo sin [tex]\theta[/tex]

    3. The attempt at a solution

    I didn't know exactly how to approach the problem. At first I wanted to label the y axis or normal force 180 n, set it equal to x sin 25, and solve for x. I feel like the mass of the suitcase (assume it is mass or is it weight?) has a part to play, but in reality, my teacher just does a bad job. -next step?
  2. jcsd
  3. Sep 24, 2007 #2

    Chi Meson

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    The normal force will be just enough to bring net vertical forces to zero. What are all the other vertical components of forces? (Name them)
  4. Sep 24, 2007 #3

    so wait. 180n brings vertical forces to zero?
  5. Sep 24, 2007 #4

    Chi Meson

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    Mass is not a force, it is the amount of matter (or inertia) in an object.
    Gravity is a phenomenon. The force due to gravity is called weight.

    There is one more force (component) that you have not mentioned, and

    Yes, 180 N upward, brings the net vertical force to exactly zero.
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