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Homework Help: Tension is cords

  1. Feb 21, 2008 #1
    A loudspeaker of mass 17.0 kg is suspended a distance of h = 1.80 m below the ceiling by two cables that make equal angles with the ceiling. Each cable has a length of l = 3.30 m.

    What is the tension in each of the cables?

    Tried mg sintheta^2+mgcostheat^2=c^2 but no dice.

    Anyone know anything?

  2. jcsd
  3. Feb 21, 2008 #2


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    The tension forces point along the wires. Call their magnitude T and split them into horizontal and vertical components. The horizontal components cancel and the sum of the vertical components should cancel the mg force on the speaker.
  4. Feb 22, 2008 #3


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    The two (similar in magnitude tensions) and the weight form a triangle. If theta is the angle between the cables and the ceiling then the angle between the two tension vectors in the triangle is two times theta.
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