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mj123
Feb15-10, 05:29 PM
A rod weighs 180 lb and has a 400 lb load located at point A is suspended in the air by two lines runningfrom point A to points C and D and a ball and socket joint at E. Find the forces for the tension in eachline (rope?, cable?) (A to C and A to D) and the forces at the ball and socket joint.


I figured out the tensions.. but the ball and socket its confusing

nvn
Feb15-10, 08:48 PM
mj123: The PF rules state we are not allowed to tell you how to approach or solve your homework problem. See the required homework template that appears when you start to create a new thread in the homework forums. You must list relevant equations yourself, and show your work; and then someone might check your math. Also, you would need to show a diagram of the problem.

mj123
Feb15-10, 09:17 PM
sorry.. I figured out that TAD=TAD[-.6506-.390+.6509] and TAC=TAC[.394-.4728+.788]

then i know that i have to find Bx,By and Bz. But I am kind of stuck there 'cause im not sure how the 180lb and the 400lb influence in the whole problem

http://www.mech.utah.edu/~me1300/CP1.pdf

mj123
Feb15-10, 09:34 PM
the diagram is here: http://www.mech.utah.edu/~me1300/CP1.pdf

nvn
Feb16-10, 12:30 AM
mj123: Maintain at least four, preferably five, significant digits for all your intermediate calculations. Use the static equilibrium equations, such as summation(Fx) = 0, summation(Fy) = 0, summation(Fz) = 0, summation(Mx) = 0, to solve simultaneously for the unknowns. If you show your work, someone might check your math.

pongo38
Feb16-10, 02:56 PM
Draw a free body diagram (FBD) similar to the given figure ( I assume there is a mistake and B is the same as E). On the FBD, draw all the forces that act on it, including at the ball joint. Then make equilibrium statements from which you can extract your answers.