In the figure, a constant horizontal force Upper F Overscript right-arrow EndScripts Subscript app of magnitude 6.6 N is applied to a wheel of mass 10 kg and radius 0.20 m. The wheel rolls smoothly on the horizontal surface, and the acceleration of its center of mass has magnitude 0.42 m/s2.
(a) What is the magnitude of the frictional force on the wheel?
(b) What is the rotational inertia of the wheel about the rotation axis through its center of mass?