A spool of wire of mass M and radius R is unwound under a constant force F (Fig. P10.85). Assuming the spool is a uniform solid cylinder that doesn€™t slip, show that
(a) The acceleration of the center of mass is 4F/3M and
(b) The force of friction is to the right and equal in magnitude to F/3.
(c) If the cylinder starts from rest and rolls without slipping, what is the speed of its center of mass after it has rolled through a distance d?

Figure P10.85