Basics of Equilibrium

[CSCPE24]

Hi All,

Just a trivial question. I'm trying to prepare for a PE exam and came across a sample question that seems to escape me. I just need a nudge in the correct direction.

I've enclosed the diagram to the problem. It is asking me to find the magnitude, direction, and distance from point A of the force required to act on the rigid body shown to hold it in equilibrium.

Summing forces in X and Y directions solves for the Magnitude and Direction of the force. Summing moments about point A also gives me 13Y + 14X - 468 =0. However, what am I missing to find another equation with respect to X and Y so I can solve for them? X & Y are the distances from point A respectively.

Any help is greatly appreciated.

Thanks in Advance....

 

[rb1957]

but it makes me wonder about how these exams are marked ... "right" answer = full marks, correct solution but not "right answer" is less ?, does the marker have time to work through the solution provided ??

 

[Cockroach]

I think posted solutions work the best. A number of us got the same answer.

Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada

 

[CSCPE24]

Thank you all for the great discussion.

This has been a rather interesting problem because of the nature of the solution set provided.

 

[IDS]

Cockroach - The solution in your attached file gives the right magnitude and direction of the reaction force, which comes straight from the resolution of forces, but you can't apply it just anywhere. If you take moments about F you will see that you don't have equilibrium.

Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/