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STATICS - CASE STUDY

    Introduction


Pulley Failure in the Factory
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A pulley assembly is used to move heavy objects around a factory floor. As the assembly moves, the total force on the main pulley changes. At a certain angle, the main pulley fails from the tension in the cable.

What is known:

  • The forces on the pulley at failure are as follows:

    (1) F1 = 500 lb downward
    (2) F2 = 500 lb, 30° from downward
   
    Question


Pulley Force Diagram

 

What is the total force on the pulley and in what direction does it act?

   
  Approach

 
  • Solve for the rectangular components of the two forces on the pulley.
  • Combine the two forces using vector addition to find the total force exerted on the pulley.
  • Solve for the magnitude and direction of the total force.