Auniform wheel of mass 12 kg and radius 0.4 m is mounted rigidly on a massless axle through its center. the radius of the axle is 0.2 m, and the rotational inertia of the wheel-axle combination about its central axis is 0.6 kg m2 . the wheel is initially at rest at the top of a surface that is inclined at angle =30o with the horizontal. the axle rests on the surface while the wheel extends into a groove in the surface without touching the surface. once released, the axle rolls down along the surface without slipping. when the wheel-axle combination has moved down along the surface by 5 m, what is its center-of-mass velocity?