## College Physics (4th Edition)

(a) We can find the ratio of the final magnitude of the momentum to the initial magnitude of the momentum: $\frac{p_f}{p_0} = \frac{mv_f}{mv_0} = \frac{3v_0}{v_0} = 3$ The ratio of the final magnitude of the momentum to the initial magnitude of the momentum is 3 (b) We can find the ratio of the final kinetic energy to the initial kinetic energy: $\frac{KE_f}{KE_0} = \frac{\frac{1}{2}mv_f^2}{\frac{1}{2}mv_0^2} = \frac{(3v_0)^2}{v_0^2} = 9$ The ratio of the final kinetic energy to the initial kinetic energy is 9