Suspending a Weight with 3 Cords: A Puzzle

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fisselt
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Homework Statement


Weight suspended by 3 cords. 1 from the weight goes up vertically to the knot. The next goes left 30° below horizontal and the last goes to the right 45° above horizontal.

Homework Equations


f=ma


The Attempt at a Solution


I don't think I've ever worked a problem with a cord below horizontal. So I'm stumbling a bit.

Since there's only 1 cord above horizontal (T1) it should carry the whole y force. So, in y T1=T2+T3
And, in x the left and right cords must be equal T1=T2


T1sin(45)=T2sin(30)+mg

Not sure about the rest. Any help?
 
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The problem statement is somewhat confusing. A figure would really help.
 
Quick picture I just made.
 
Attachments
  • Hand-drawn diagram of a box labelled W hanging from a junction point by a vertical cord, with two cords running to a wall on the left and a ceiling beam on the right. The left cord makes 30 degrees with a dashed horizontal line and the right cord makes 45 degrees with the ceiling.
    Tension.jpg
    9.1 KB · Views: 540
As the object not going up or down
it's too not going left or right, equal forces must be there to make it in equilibrium.
 
You simply need to sum forces, both horizontal and vertical, at the junction point, and require that both sum to zero. That will give you everything you need.