A gun is so designed that, on firing, the barrel recoils against a spring. A dashpot, at the end of the recoil, allow the barrel to come back to its initial position within the minimum time without any oscillation. The gun barrel has a mass of 500 kg and a recoil spring of 300 N/m. The barrel recoils 1 m on firing. Determine the (i) initial recoil velocity of the gun barrel, and (ii) critical damping coefficient of the dashpot engaged at the end of the recoil stroke.