Static Equilibrium and tension of a cord

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A non-uniform bar weighing 12.5 N is suspended horizontally by two massless cords, with cord 2 at a 27.5° angle to the vertical. The center of gravity is located 4.4 m from the left end of the 6.0 m bar. The equations for horizontal and vertical forces (Fx and Fy) are set up correctly, but there is confusion regarding the torque equation. The torque should consider the correct length from the pivot point, which is 4.4 m for the center of gravity, and the dimensions must align properly. Clarification on the torque equation is needed to ensure it accurately represents the forces acting on the bar.
chaotixmonjuish
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A non-uniform bar of weight W = 12.5 N is suspended at rest in a horizontal position by two massless cords. The angle φ between cord 2 and the vertical is equal to 27.5°. The bar has a length L = 6.0 m and the distance of its center of gravity from the left-hand end of the bar is 4.4 m. What is the tension in cord 2?
img:http://i242.photobucket.com/albums/ff106/jtdla/prob01a-2.gif

My lab partner and I set up this equation:
Fx: T2*cos (27.5)-T1*cos(theta)=0
Fy: T2*sin(27.5)+T1*sin(theta)-mg=0

Torque: -mgL-T2*cos(27.5)=0

I'm not sure if that L is 4.4 or 6, nor do I know if I am starting this properly.
 
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Eqn for Fx and Fy are correct, but torque is incorrect; firstly, dimensionally its wrong and secondly, which is cord 1? left side one or right side one?
 
Cord 1 is on the left
 
k. then L should be 4.4
 
so is the torque equation correct if i use 4.4
 
dimensionality?
 
I'm afraid I don't understand
 
chaotixmonjuish said:
Torque: -mgL-T2*cos(27.5)=0
T2*cos(..) has dimensions of force and mgL has dimensions of work.
 
so would torque be the length of the bar*-mg
 
  • #10
torque is : -mgL + T2cos(27.5)*6 (6 is the perpendicular distance of force vector from the point at which you are taking torque)
 
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