2d statics truss, joint method

[togo]

Homework Statement

Determine force of each member using joint method

Homework Equations

T = F x D

The Attempt at a Solution

Answers are:

Fab 2465 T
Fbd 1200 T
Fbc 1375 C
Fdc 750 C
Fde 860 T (This one is what I tried)
Fce 649 C
Fac 1922 C

Thanks.

 

[vela]

I moved this thread to the engineering homework forum as you're more likely to get responses on this type of problem there.

You might want to forgo using a scanned image of your work, especially one so large, since it makes your post inconvenient to read.

 

[PhanthomJay]

Determine force of each member using joint method

Homework Equations

T = F x D

The Attempt at a Solution

Answers are:

Fab 2465 T
Fbd 1200 T
Fbc 1375 C
Fdc 750 C
Fde 860 T (This one is what I tried)
Fce 649 C
Fac 1922 C

Thanks.

You have the wrong geometry for the slope of member DE...the rise is 20 but the run is 25, not 55...

Always determine joint support reactions first using the equilibrium equations; then start at the easiest joints next when determining forces using the method of joints. Also be sure to indicate T (force of member on joint pulls away from joint) or C (force of member on joint pushes toward joint).

 

[togo]

thanks for that, encouraging to know I'm on the right track. Something did seem wrong with the trig

 

[DeeNos]

I would like to point out that the joint method is a commonly used approach in structural engineering to analyze the forces in a truss system. It involves isolating a specific joint and applying the equations of static equilibrium to determine the forces in each member connected to that joint. The equation used in this method is T = F x D, where T is the tension or compression force in a member, F is the external force acting on the joint, and D is the length of the member.

Based on the provided answers, it seems that the homework problem involves a 2D statics truss, which means that the truss is only loaded in the x-y plane and there is no movement in the z-direction. It is important to note that the answers may vary depending on the specific dimensions and loads of the truss. Therefore, it is crucial to carefully follow the steps of the joint method and double-check the calculations to ensure accuracy.

In conclusion, the joint method is a useful tool for analyzing truss systems and determining the forces in each member. It is a fundamental concept in structural engineering and is essential for designing safe and efficient structures. As a scientist, it is important to always approach problems with careful analysis and attention to detail.