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Homework Help: Tension and Reactions

  1. Oct 25, 2008 #1
    Tension = 386lb
    Bx = 493lb
    By = 186lb

    I am having trouble trying to determine the tension in the picture. And the x and y component of B

    i have a long bar that is 14 feet long. it is connected at 1 end at point B to a pin support and the other end is tied to a rope at point a.point a the rope has a angle of 30 degrees off of vertical. then i have a downward force of 600 N 30 degrees of the vertical 9 feet away from point B. how do i find the tension in the rope ?

    the componets of the 600n force are as follows
    -600sin30 = -300
    -600cos30 = -519.615
    if the rope is 5 feet from these componets how would i find the tension ? and what would be the reaction on point B ?

    reaction of By = (-600cos30*5ft)/14ft = 185.6lb = 186lb
    how do you find Bx and the tension at rope ?
    Last edited: Oct 25, 2008
  2. jcsd
  3. Oct 25, 2008 #2
    Does anyone know how to find the answers ?

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  4. Oct 25, 2008 #3


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    You determined By apparently by summing moments about A (unless you did it by trial and error). Now sum moments about B to determine Ay (the vertical component of the tension). Or sum the Fy forces = 0 to get Ay. The horizontal forces and rope tension can then be found. How is the rope tension and its vertical component related?
  5. Oct 25, 2008 #4
    The forces are yet unknown at two points, namely tension T at A and reactions at B.
    Take moments about B to find the tension T of the rope.
    Once T is know, summing forces in X and Y will give you everything you need to know for the reaction at B.
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