The 10-lb cannon ball is fired horizontally by a 500-lb cannon as shown. If the muzzle v...

The 10-lb cannon ball is fired horizontally by a 500-lb cannon as shown. If the muzzle velocity of the ball is 2000 ft/s, measured relative to the ground, determine the recoil velocity of the cannon just after firing. If the cannon rests on a smooth support and is to be stopped after it has recoiled a distance of 6 in, determine the required stiffness k of the two identical springs, each of which is originally unstretched.