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Homework Help: Two Ball Tension

  1. Feb 15, 2010 #1
    The problem statement, all variables and given/known data
    Two identical 11.1kg balls, each 28.4cm in diameter, are suspended by two 35.0cm wires as shown in the figure . The entire apparatus is supported by a single 18.0cm wire, and the surfaces of the balls are perfectly smooth.

    a)Find the tension in the top wire.
    b)Find the tension in each of two bottom wires.
    c)How hard does each ball push on the other one?


    The attempt at a solution
    I found the correct answer to part a (218N) by F=mg. I am stuck on part b and c. I have found the angles to the corresponding triangle the balls and string make. The top angle is 47.872deg and the bottom two are both 66.064deg. Taking the cosine of 1/2 the top angle and dividing by the weight of a single ball is what I would've though to yield the tension in the diagonal strings, but I was wrong with 119N. Can anybody enlighten me or point me in the right direction?
  2. jcsd
  3. Feb 15, 2010 #2
    Yes, I actually have the same problem. Could someone help us please?
  4. Feb 15, 2010 #3
    Even if no one responds by midnight, when this is due, I still want to know how to do this.
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