## Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (3rd Edition)

(a) $\alpha = -100~rad/s^2$ (b) $\alpha = 0$ (c) $\alpha = 50~rad/s^2$
The angular acceleration is equal to the slope of the angular velocity versus time graph. (a) At t = 1 s: $\alpha = \frac{\Delta \omega}{\Delta t}$ $\alpha = \frac{-200~rad/s}{2~s}$ $\alpha = -100~rad/s^2$ (b) At t = 3 s: $\alpha = 0$ (c) At t = 5 s: $\alpha = \frac{\Delta \omega}{\Delta t}$ $\alpha = \frac{150~rad/s}{3~s}$ $\alpha = 50~rad/s^2$