How to determine which point to take the moment about?

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Homework Help Overview

The problem involves a T-shaped bracket supported by a wheel and pegs, requiring the determination of reactions at specific points when subjected to a 30-degree angle. The original poster expresses confusion regarding the choice of point for taking moments, specifically between points E and D.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to understand the implications of taking moments about different points, questioning the rationale behind the suggested choice of point D over point E.

Discussion Status

Some participants have provided guidance on the benefits of selecting specific points for moment calculations, suggesting that it may simplify the process and reduce errors. The discussion reflects an exploration of different approaches without reaching a consensus.

Contextual Notes

The original poster has not provided visual aids or a detailed solution, which may limit the clarity of the discussion. There is an emphasis on understanding the principles of equilibrium and moment summation in the context of the problem.

CCenturion
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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
 

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See template for homework section.
You did not show neither the problem nor your solution.
 
CCenturion said:
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
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.
 
Got it Phantom, Thanks a lot !
 

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