Two collars and a fixed shaft, required friction?

[JFUNR]

Homework Statement

Two collars A and B can slide on vertical rods. Collar A and collar B are connected by a cord that passes over a fixed shaft at C. the static friction coefficient of any two contact surfaces is 0.2. the weight of collar B is 10 lb, neglect collar A's weight, determine the range of force F required to maintain the equilibrium.

Homework Statement

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Homework Equations

The Attempt at a Solution

 

[LawrenceC]

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