1. The problem statement, all variables and given/known data A submarine of mass 2.5 x 10^6 kg and initially at rest fires a torpedo of mass 260 kg. The torpedo has an initial speed of 100.4 m/s. What is the initial recoil speed of the submarine? Neglect the drag force of the water. 2. Relevant equations m1v1=-m2v2 3. The attempt at a solution mass one = 2.5x10^6 (submarine) velocity one = 0 (sub isnt moving) mass two = 260 (torpedo) velocity two = 100.4 (torpedo) How can I find the recoil? I thought maybe it'd just be velocity one (instead of zero solve for x) v1 = (260*100.4)/2.5x10^6 = -0.01 m/s But that's wrong... what am i missing?