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Homework Help: Net Force: Tension problems with angles

  1. Aug 24, 2010 #1
    1. The problem statement, all variables and given/known data
    A rope forms a Y.

    At the end of the Y hangs a block with a W= 100N
    Whole the two upper ends are on the walls.
    (Left side) [tex]T{1}[/tex] with an angle of 90 degrees
    (Right side) [tex]T{2}[/tex] with an angle of 58 degrees

    Find the tension of each rope on the wall.
    2. Relevant equations
    No definite formulas


    3. The attempt at a solution
    [tex]\Sigma[/tex]Fx=[tex]T{1}[/tex]cos90-[tex]T{2}[/tex]cos58=0
    Summation of Fy=Tsub2sin58-100=0
    =117.92

    cos90=0
    Which makes the value of [tex]T{1}[/tex] an error.
    Where did I go wrong?
     
    Last edited: Aug 24, 2010
  2. jcsd
  3. Aug 24, 2010 #2

    kuruman

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    Without a picture, it is hard to imagine what is going on. How are the angles measured? With respect to the vertical or with respect to the horizontal?
     
  4. Aug 24, 2010 #3
    Oh sorry...
    T1 is measured respect to the vertical
    T2 respect to the horizontal

    As for the picture ill try to provide but erm its like this:
    Your left pointing finger must form a right angle with your right pointing finger such that your nails/tips are touching each other.

    Then T1 is attached on your left pointing finger.
    And T2 is attach on your right pointing finger.
     
  5. Aug 24, 2010 #4
    p4_11alt.gif

    oh its like this but instead of a ninja...its a block
     
  6. Aug 24, 2010 #5

    kuruman

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    OK. So it looks like in the x-direction you have two components of forces. Since the force on the left T1 is entirely in the x-direction (has no y-component), what is its x-component? What about the x-component of T2?
     
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