You are to design a rotating cylindrical axle to lift 800 n buckets of cement from the ground to a rooftop 78.0 m above the ground. the buckets will be attached to a hook on the free end of a cable that wraps around the rim of the axle; as the axle turns, the buckets will rise. if instead the axle must give the buckets an upward acceleration of 0.400m/s2, what should the angular acceleration of the axle be?