A 28.0-kg block is connected to an empty
2.00-kg bucket by a cord running over a frictionless pulley (Fig. 5-52). The
coefficient of static friction between the table and the block is 0.45 and the
coefficient of kinetic friction between the table and the block is 0.32. Sand
is gradually added to the bucket until the system just begins to move. (a)
Calculate the mass of sand added to the bucket. (b) Calculate the acceleration
of the system.