1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

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 ?

    Attached Files:

    • asd.bmp
      File size:
      248.1 KB
  4. Oct 25, 2008 #3


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    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.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook