A solid aluminum sphere of radius 3 in. is welded to the end of a 6-in.-long rod AB of negligible mass which is supported by a balland-socket joint at A. Knowing that the sphere is observed to precess about a vertical axis at the constant rate of 60 rpm in the sense indicated and that rod AB forms an angle ß = 30° with the vertical, determine the rate of spin of the sphere about line AB.
