Chapter 9, Problem 69GP

* You have an empty cylindrical metal can and two metal nuts. In your first experiment, you spin the can around its axis and place it on a rough table (Figure P9.69). The can slows down due to friction, with the rotational acceleration ${\alpha }_1=30{\text{ rad/s}}^{\text{3}}$ until it stops rotating in your second experiment, you first fix two nuts near the center of the can (Figure P9.69D) and spin it again before placing it on the table in this case, the can slows down with the rotational acceleration ${\alpha }_1=38{\text{ rad/s}}^{\text{2}}$ in your third experiment. you spin the can with the nuts fixed at opposite sides of the can (Figure P9.69c). Now the can slows down with rotational acceleration ${\text{α}}_{\text{3}}{\text{=26 rad/s}}^{\text{3}}$. Explain (a) why ${\alpha }_2>\alpha$, (b) why ${\alpha }_2<{\alpha }_2$, and (c) why ${\alpha }_3<\alpha$.