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Homework Help: Free Body Diagram?

  1. Feb 26, 2008 #1
    1. The problem statement, all variables and given/known data
    http://img258.imageshack.us/img258/7172/testiiifo2.jpg [Broken] Here is an image of the problem (taken from a practice test.)

    2. Relevant equations

    3. The attempt at a solution
    I drew the free body diagrams for each, but I have no idea what the equation would be. I came up with equations for each mass, and solved for a in one, plugged into the other and got this.

    Tension Force (string, m2) - Grav Force (earth, m2)=M2*((-tension force string, M1)/m1)

    This doesn't appear to me to be a position equation.. please help.
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Feb 26, 2008 #2
    If this is not descriptive enough, please let me know and I'll run to my friend's house and scan my work.
  4. Feb 26, 2008 #3
    Well, if you draw the free body diagram for figure 2, you simply have for each part, the one sitting on the table is:

    Tension = m1 * a

    The one hanging is:

    mg - Tension = m2 * a

    Plug in for the tension:

    mg - m1 a = m2 * a
    mg = (m1+m2) a
    a = m/(m1+m2) * g

    So you would need to plot m/(m1+m2) on the x axis. Hope this helps.
  5. Feb 26, 2008 #4
    Yes, thank you much Runelord :-D
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