How Do You Calculate the Tension in the Cable Supporting a Pivoted Steel Bar?

[hooper.d]

Homework Statement

A 365 kg mass is supported on a wire attached to a 15 m long steel bar that is pivoted at a 10 meter vertical wall and supported by a cable. The mass of the bar is 100 kg. (Take right and up to be positive.)
With the cable attached to the bar 5.0 m from the lower end find the tension in the cable. The angle between the wall and the rod is 60 degree.

Homework Equations

equilibrium equations

The Attempt at a Solution

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[da_nang]

Setup a free body diagram, with the appropriate forces. You'll most likely need to assume the wire and cables are massless. Now this system is in equilibrium, the net force and net torque is zero. For the net force, divide the forces into components and use Newton's second law of motion. To get the tension, set up appropriate equations with the formulas for net torque. Remember to choose a pivot point. With a well chosen pivot point, you don't need to consider some of the torque.