A bead lies on a frictionless hoop of radius R that rotates around a vertical diameter with constant angular speed ω, as shown in the figure below.
Figure 1
(a) What should ω be so that the bead maintains the same position on the hoop, at an angle θ with respect to the vertical? Express you answer in terms of some or all of the following: θ, R and g.
(b) Analyzing the answer for Part A, you will find that there is a range of angular speeds, 0 < ω < ω0 for which the fixed angle θ = 0 (meaning that the only balanced position is at the bottom of the hoop). Find the value of ω0. Express you answer in terms of some or all of the following: R and g.