A cannon of mass 5.17 x 10 3 kg is rigidly bolted to the earth so it can recoil only by a negligible amount. The cannon fires a 74.3-kg shell horizontally with an initial velocity of 542 m/s. Suppose the cannon is then unbolted from the earth, and no external force hinders its recoil. What would be the velocity of a shell fired from this loose cannon?
(Hint: In both cases assume that the burning gunpowder imparts the same kinetic energy to the system