Chapter 10, Problem 2Q

Figure 10-21 shows plots of angular position θ versus time t for three cases in which a disk is rotated like a merry-go-round. In each case, the rotation direction changes at a certain angular position θ_change. (a) For each case, determine whether θ_change is clockwise or counterclockwise from θ = 0, or whether it is at θ = 0. For each case, determine (b) whether ω is zero before, after, or at t = 0 and (c) where α is positive, negative, or zero.

Figure 10-21 Question 2