## Fundamentals of Physics Extended (10th Edition)

Angle it rotates in coming to rest $= 18.9$ $rad$
The formula to be used here is: $\omega_{f}^{2} = \omega_{o}^{2} + 2\alpha(\theta-\theta_{o})$ By arranging the equation, we make $(\theta-\theta_{o})$ the subject of formula: $(\theta-\theta_{o}) = \frac{\omega_{f}^{2}-\omega_{o}^{2}}{2\alpha}$ Substituting the values in formula and solving: $(\theta-\theta_{o}) = \frac{0^{2}-(12.6)^{2}}{2\times (-4.2)}$ $(\theta-\theta_{o})=18.9$ $rad$