Chapter 12, Problem 26P

A uniform sphere of radius R is supported by a rope attached to a vertical wall, as shown in Fig. 12.18. The rope joins the sphere at a point where a continuation of the rope would intersect a horizontal line through the sphere’s center a distance $\frac{1}{2}$R beyond the center, as shown. What’s the smallest possible value for the coefficient of friction between wall and sphere?

FIGURE 12.18 Problem 26