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How to determine which point to take the moment about?

  1. Oct 21, 2014 #1
    Problem -
    1. The T-shaped bracket shown is supported by a small wheel at E and pegs at C and D. Neglecting the effect of friction, determine the reactions at C, D, and E when the angle is 30 degrees.

      I have taken the moment about E, and gotten a result for all the reactions. However, in the solutions it says that i should be taking the moment about D.
      I don't understand what the difference is between picking one point or the other.
      Please refer to the two attached pictures. Thank you
     

    Attached Files:

    Last edited: Oct 21, 2014
  2. jcsd
  3. Oct 21, 2014 #2
    See template for homework section.
    You did not show neither the problem nor your solution.
     
  4. Oct 22, 2014 #3

    PhanthomJay

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    For a system in equilibrium, you can sum moments about any point = 0, but you can simplify the number of steps and reduce chances for errors when summing moments about a selectively chosen point. You might want to first solve for Ex and Ey, then sum moments about D (or C) to see how this works.
     
  5. Oct 22, 2014 #4
    Got it Phantom, Thanks a lot !
     
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