Uniform Beam (equivalent systems)

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SUMMARY

The discussion focuses on analyzing a uniform beam subjected to multiple forces, specifically determining the equivalent single force and moment at point B. The forces include a 500N force at 60 degrees, a 200N force in the j direction, and a -100N force in the i direction. The resultant force calculated is 350i - 233j N, with a moment of 350Nm at point B. The equivalent system can be reduced to a singular force, with the line of action determined to be 5/6m to the left of point B, based on the moment-to-force relationship.

PREREQUISITES
  • Understanding of static equilibrium principles, including sum of forces and moments.
  • Familiarity with vector decomposition of forces.
  • Knowledge of calculating moments about a point in a beam.
  • Proficiency in using the equation d = M/F for determining distances in statics.
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  • Study the principles of static equilibrium in greater detail.
  • Learn about vector decomposition techniques for forces in engineering mechanics.
  • Explore the concept of equivalent force systems in statics.
  • Investigate the applications of the moment-to-force relationship in beam analysis.
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Engineering students, structural analysts, and professionals involved in mechanical and civil engineering who are working on beam analysis and static equilibrium problems.

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Homework Statement
A uniform beam |AE| at 2m from A there's a 500N force at 60degrees to the negative x-axis direction. At 3.5m from A (1.5m from the 600N) There's a 200j N force and at 4.5m from A there's a -100i N force acting 0.5m above the beam.


i)Determine the single force which is passing through B (2m from A) and the resuting moment which is equivalent

ii)Reduce the system in i to a singular force (no couple) and determine where its line of action lies on AE using A as a point of reference for distance

(THis is B in the attached PDF)

Homework Equations


For equilibrium:
sum of forces=0
sum of moments=0

The Attempt at a Solution


i)
The 600N force can be broken down to 500Cos60 i - 500sin j = 250i-433j N
Sum of forces in Y= -433+200=-233
Sum of forces in X= 250+100=350
Sum of moments about B= 200(1.5)+100(0.5)=350Nm
Therefore, the equivalent system is 350i-233j N and a 350Nm moment at B.
ii)
I'm not very sure about this. Can I move the moment a certain distance so that it become a force of 350/(some distance from B)
Edited:
I found an equation which says d=M/F (moment divided by resultant force) so in this case it would be 350/(350i-233j)
so would that be 350/420=5/6 m but to which side of B? is 5/6m to the left since its a positive moment. (Anti-clockwise being positive)
 

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If I remember my statics correctly, you have to combine the forces into one resultant force that satisfies the following conditions:

1. The components of the resultant force in x and y must equal the sum of the individual forces in x and y.
2. The resultant force must act at a place on the beam so that the moment at B is the same as in part (i).

Try that and see what comes out.
 

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