1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: 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


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    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 !
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted