long, straight, thin rod is tilted by an angle above the horizontal. The rod is then rotated about a vertical axis while keeping the lower end fixed, such that the rod traces out a cone as it rotates at an angular velocity . A bead (with a hole in it) is placed on the rod, and can slide without friction along the rod. Is is possible for the bead to be in equilibrium on the rod as it goes around? If so, find the necessary conditions. Assume gravity acts downward in the usual sense. Cont