A yoyo of mass m=1 kg and moment of inertia ICM=0.045 kg m2 consists of two solid disks of radius R=0.3 m, connected by a central spindle of radius r=0.225 m and negligible mass. A light string is coiled around the central spindle. The yoyo is placed upright on a flat rough surface and the string is pulled with a horizontal force F=20 N, and the yoyo rolls without slipping.

(a) What is the x-component of the acceleration of the center of mass of the yoyo? (in m/s2)

a=
(b) What is the x-component of the friction force? (in N)

f=