Michaela lives near the railroad tracks and often hears the loud bangs associated with cars being added to trains. when a friend of hers is visiting, the friend becomes alarmed at the sounds, wondering what they are but michaela is able to reassure her friend that it is a normal train-related sound. michaela's skills, at least in this situation, are superior to her friend's.

Two steel balls, each of mass m, are welded to a light rod of length l and negligible mass and are initially at rest on a smooth horizontal surface. a horizontal force of magnitude f is suddenly applied to the rod as shown. determine (a) the instantaneous acceleration a of the mass center g and (b) the corresponding rate at which the angular velocity of the assembly about g is changing with time.