Equilibrium of weight on pulley

AI Thread Summary
To achieve equilibrium in the pulley system with a 15lb weight and a counter-force of 17lb, the tension in the cable must be calculated based on the forces acting on both weights. The problem lacks angle measurements, complicating the analysis of the forces and the resultant tension. A force diagram is necessary to visualize the forces acting on the 15lb weight. The tension cannot simply be assumed to be 32lb, as it must be derived from the equilibrium conditions of the 17lb mass. Understanding the relationship between the weights and the angles is crucial for solving the problem accurately.
drkidd22
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Homework Statement



A 15lb weight at a on frictionless rod at a distance of 16" from a pulley can move up and down and it has counter-force on pulley of 17lb. What should the height of weight on rod be so that system is in equilibrium


Homework Equations



Cosine Law
Sine Law

The Attempt at a Solution



I have tried to draw the problem so that it would be better to understand. I'm not given any angles and not sure to get started here.
 

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What's the tension in the pulley cable? What angle must the cable make with respect to the weight on the rod. (Redo your force diagram to show the forces acting on the 15lb weight.)
 
I'm having difficulty trying to understand the problem as is. The tension in the cable would be the sum of all components of both weights, but I'm not given angles to find them. Wouldn't the tension be 32lb anyways?
 
drkidd22 said:
The tension in the cable would be the sum of all components of both weights,
No, that's not true.
but I'm not given angles to find them. Wouldn't the tension be 32lb anyways?
No.

To find the tension in the cable, analyze the forces acting on the 17lb mass. That mass must be in equilibrium also.
 
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