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Homework Help: Need Help In Getting Started

  1. Oct 18, 2004 #1
    In my statics class we are studying Rigid body equilibrium and when it got to 3D I get a little lost. Below are some homework questions I'm having a hard time starting. I get the free body diagrams but don't know where to go from there. I find that there are more unknowns than I have equations for.

    I have provided links for the reactions that happen at certain types of connections. I also apologize for the bad scanning job on a couple of the images.

    http://herograw.com/reactions1.JPG [Broken]
    http://herograw.com/reactions2.JPG [Broken]

    http://herograw.com/5-80.JPG [Broken]
    http://herograw.com/5-84.JPG [Broken]
    http://herograw.com/5-96.JPG [Broken]

    I appreciate any help. I need to finish this assignment asap.
    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Oct 18, 2004 #2


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    Are you remembering to account for Torque?
  4. Oct 18, 2004 #3
    I am accounting for moments (tourque). The 6 equations that I have to use are:

    1) Force Equations:
    -[tex]\Sigma F x =0[/tex]
    -[tex]\Sigma F y =0[/tex]
    -[tex]\Sigma F z =0[/tex]

    2) Moment Equations
    -[tex]\Sigma M x =0[/tex]
    -[tex]\Sigma M y =0[/tex]
    -[tex]\Sigma M z =0[/tex]
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