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Tension of 10 m rope hung across 6 m horizontal distance with 50 kg box hanging

  1. Nov 4, 2011 #1
    1. The problem statement, all variables and given/known data
    A rope is 10.0 m long and is attached at points A and B, which are at the same elevation 6.0 m apart. If a 50.0 kg mass is attached to the rope 4.0 m away from point A, what is the tension in the two segments of the rope?

    2. Relevant equations
    W = ma
    ƩFy = 0 = T1 + T2 - W
    ƩFx = 0 = T1 + T2

    3. The attempt at a solution
    W = 50.0 kg * 9.81 m/s^2
    I'm stuck after finding the weight of the hanging mass as no other angles or forces are given? I tried using 6.667 m and 3.333 m as the respective lengths for T1 and T2 assuming that the ratio of 2/3 distance of the hanging mass between point A and B would be the same ratio on the rope length. Then tried to use trig to get the vertical hanging distance but came up with 2 different distances so these numbers don't work. I'm lost and stuck as to were to go. Any help is much appreciated as this homework assignment is already late and I've spent about 5 hours reading and looking up stuff online with no success! Feel as though I'm trying to extract blood from a rock!
    Last edited: Nov 4, 2011
  2. jcsd
  3. Nov 4, 2011 #2


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    Not only must your forces balance, you must also have 10 m of rope between A, the load, and B.
  4. Nov 4, 2011 #3
    Yes that is correct. Not sure if that was a statement or a question, but I'm past that part, drew my diagram and am stuck trying to suck Newtons out of meters and no angles somehow???
    Last edited: Nov 4, 2011
  5. Nov 4, 2011 #4
    I think I figured it out... I was interpreting the problem to mean that the mass is 4 m horizontal distance from point A, but I think that the 4 m was supposed to be the length of T1 or the hypotenuse for my right triangle! If only story problems came with pictures! Thanks for you're reply SteamKing I'll be back if I hit another wall but I should be good for this problem now.
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