Finding FA, FB, FC, FD in 3D Static Equilibrium

  • Thread starter aoide
  • Start date
  • Tags
    3d Static
In summary, the conversation discusses how to find FA, FB, FC, FD in 3D equilibrium static, including the use of W1 = 500kg and the distance from the center of the table. The solution is relatively simple if the load is in the center of the table, but becomes more complex in 3D. The use of symmetrical loading and equations of equilibrium are also mentioned. It is recommended to post future questions in the General Engineering forum rather than sending private emails.
  • #1
aoide
3
0

Homework Statement



how to find FA, FB, FC, FD in 3D equiblirium static?

Homework Equations



W1 = 500kg

[URL]http://www.flickr.com/photos/djaguank/5450648168[/URL]

distance (see at image)
if you can't see the image, please follow this link

http://www.flickr.com/photos/djaguank/5450648168

The Attempt at a Solution

 
Last edited by a moderator:
Physics news on Phys.org
  • #2
I didn't see much of an attempt. Is the load in the center of the table? If no, forget about finding the reactions without a computer program or a copy of Roarke's 'Stress and Strain". If yes, the solution is relatively simple.
 
  • #3
PhanthomJay said:
I didn't see much of an attempt. Is the load in the center of the table? If no, forget about finding the reactions without a computer program or a copy of Roarke's 'Stress and Strain". If yes, the solution is relatively simple.

yes.. its in the center.. could you tell me how to solve it?? because, i confused about 3D static..

anyway.. do you have any recomendation for 3D static equil book??

thanks
 
  • #4
If it's in the center, is there any reason to believe that the force in one leg will be greater than any other, if the table sits on level floor and its legs are identical in lenght? The loading is symmetrical. Most books on statics touch on 3D, which is at a level of difficulty greater than 2D. In 3D, You are dealing with more equations of equilibrium, since there are 3 axes inolved. The particular plate problem is generally statically indeterminate if the load is not centered.
 
  • #5
@phantom

thanks for your explanation, i think i start to get the idea..

anyway, how about picture in this link..

http://www.flickr.com/photos/djaguank/5452658183/

could it use symetrical?? COG for body and antenna in middle.. but the leg/support not in same plane (see picture from above)

do you have email?? i want to ask you some question, please send your email to g.ghunk.np@gmail.com

thanks again
 
  • #6
aoide said:
@phantom

thanks for your explanation, i think i start to get the idea..

anyway, how about picture in this link..

http://www.flickr.com/photos/djaguank/5452658183/

could it use symetrical?? COG for body and antenna in middle.. but the leg/support not in same plane (see picture from above)

do you have email?? i want to ask you some question, please send your email to g.ghunk.np@gmail.com

thanks again
It appears that the outrigger supports are symmetrical about the axes of the plane, in which case you could represent the loading as equivalent forces and couples appied at the COG, and compute reaction forces at the 4 supports by looking at the components of the loading about each respective axis, computing the reactive forces accordingly by applying the equilibrium equations in each direction (noting due to symmetry that the loading is shared equally by the near and far supports), then add them up algebraically (a corner support may take the maximum load).
Since this does not appear to be a homework problem, you should post future questions that are not homework related in the General Engineering forum (assuming this is not homework). No private emails, please! You'll get more responses in these forums from a host of others, also.
 

FAQ: Finding FA, FB, FC, FD in 3D Static Equilibrium

How do I determine the forces FA, FB, FC, and FD in a 3D static equilibrium?

In order to determine these forces, you will first need to draw a free body diagram of the object or system in question. Next, use the equations of static equilibrium (sum of forces in x, y, and z directions equal to 0 and sum of torques equal to 0) to set up a system of equations. Finally, solve for the unknown forces using algebra or other mathematical methods.

What is the importance of finding FA, FB, FC, and FD in a 3D static equilibrium?

Determining these forces is important because it allows us to understand the stability of an object or system. It also helps us analyze and predict the behavior of structures under different loading conditions.

Can I find FA, FB, FC, and FD using only 2D equations?

No, in order to accurately determine these forces in a 3D static equilibrium, you will need to use the equations of static equilibrium in all three dimensions. Using 2D equations will not give you the complete picture and may lead to incorrect results.

Are there any assumptions made when finding FA, FB, FC, and FD in 3D static equilibrium?

Yes, some common assumptions include the object being in a state of rest, having a constant and uniform density, and all external forces and torques acting at a single point.

Are there any real-life applications of finding FA, FB, FC, and FD in 3D static equilibrium?

Yes, this concept is commonly used in engineering and design to analyze and optimize the stability and strength of structures such as bridges, buildings, and machines. It is also used in physics and mechanics to study the behavior of objects under different forces and loads.

Back
Top