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Homework Help: Equilibrium problem:

  1. Apr 3, 2007 #1
    I better introduce myself first: My name is Brian and I go to Ca state university of Chico majoring in biology. I just found this site and hope to get some help on here!

    A uniform 250 kg beam is supported by a cable connected to the ceiling, the angle of the beam resting on the floor is 40 degrees and the angle from the beam to the cable is 160 degrees. what is the tension of the cable?

    I don't know how to solve this problem with no lengths given. when i start writing out the equation I get two variables, one for tension and one for the length.
    any help would be greatly appreciated

    2. Relevant equations sum of all forces=0, sum of all torques=0

    3. The attempt at a solution[/b
    sum of all T: TmgL cos 60 -mg(L/2)-mg(L)=0
    T={mg(L/2)+ mg(L)}/ mg(L) cos 60

  2. jcsd
  3. Apr 4, 2007 #2
    sorry I can't resist the response, if it female biology you want to know, cal chico is the way to go.

    length doesn't matter. at least not here. But what does matter is an attempt to accurately state the question and your efforts to answer. So when you say the angle is 160 in the problem statement, and use 60 in your equations is it a typo or a misunderstanding of angles.
  4. Apr 4, 2007 #3
    its hard to explain without being able to show the picture but the 60 comes form the angle created from the cable and the ceiling. I should just take a picture :eek:
    Last edited: Apr 4, 2007
  5. Apr 4, 2007 #4
    that will work, use some freeware and download attachment if you can, if it is 60 degrees, is more or less parallel to the beam or crosswise?
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