Halliday, Resnick & Walker — Potential Energy and Conservation of Energy: Problem 18

18 (a) In Problem 7, what is the speed of the ball at the lowest point? (b) Does the speed increase, decrease, or remain the same if the mass is increased? Context from Problem 7: Figure 8-23 shows a thin rod, of length \( L = 2.00 \text{ m} \) and negligible mass, that can pivot about one end to rotate in a vertical circle. A ball of mass \( m = 5.00 \text{ kg} \) is attached to the other end. The rod is pulled aside to angle \( \theta_0 = 30.0^\circ \) and released with initial velocity \( \vec{v}_0 = 0 \).