A spool has a weight W = 450 lb, outer and inner radii R = 6 ft and ρ = 4.5 ft, respective...

A spool has a weight W = 450 lb, outer and inner radii R = 6 ft and ρ = 4.5 ft, respectively, radius of gyration kG = 4.0 ft, and mass center at G. The spool is being pulled to the right as shown, and the cable wrapped around the spool is inextensible and of negligible mass.

Figure P7.75

Assume that the static and kinetic friction coefficients between the spool and the ground are μs = 0.25 and μk = 0.2. Furthermore, assume that the spool is initially at rest and that the pickup truck pulls the spool with a force of 550 lb, and determine the acceleration of the center of the spool at the initial time.