What is the Tension in the Horizontal Cable Supporting a Crane?

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    Crane Static
AI Thread Summary
The discussion centers on calculating the tension in a horizontal cable supporting a crane with a 250 lb load. The crane is 25 ft long, weighs 200 lbs, and has its center of gravity 10 ft from the pivot point. Key equations for solving the problem include torque and equilibrium conditions, emphasizing that the system is static with no acceleration. Participants suggest summing torques about the pivot and considering the forces acting through their centers of mass. A request for the user to show their work indicates that further assistance requires more detailed calculations.
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crane static problem...

Homework Statement


A 25-ft. crane supported at its lower end by a pin is elevated by a horizontal cable. A 250 lb. load is suspended from the outer end of the crane. The center of gravity of the crane is 10 ft. from the pin, and the crane weighs 200 lbs. What is the Tension in the horizontal cable?

Homework Equations



t = I (alpha)
F = ma
Sums of F = 0
Sums of t = 0
r x F = t
Magnitude of t = Fdsin(theta)

The Attempt at a Solution



I have no idea, I tried doing a basic way of doing the load force mechanics but i realized it's not only that there's something with torque and the load proportion I don't know about.
 

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For a system in equilibrium, there is no acceleration, so scratch out your first 2 relevant equations. Try summing torques about the lower pivot, and note also that the weight forces act through their center of mass, and that tension forces act along the longitudinal axis of the cable (horizontally in this case). You must show some work before we can be of further assistance.
 
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