1. The problem statement, all variables and given/known data So basically I have a train with two joined carriages which become separated (m1) Mass one =13563kg and (m2) Mass two =30394kg. the initial velocity of the joined carriages is 5.00m/s (u1). When the carriages separate I have the final velocity of (m2) which is 0.96m/s (v2) Using the conservation of momentum principles I want to find the final velocity of (m1) which will be (v1) m1=13563kg m2=30394kg u1=5.00 m/s v2=0.96 m/s 2. Relevant equations I know Momentum Initial = Momentum Final and Change in momentum: = m Δv = m (v – u) and Velocity = Momentum/Mass I was thinking finding the energy values using the KE formula KE=mv^2/2 but i'm honestly a bit lost. 3. The attempt at a solution The masses together = 13563+30394 = 43957kg Total Momentum = Total Mass x Velocity; M=((m1+m2)x5.00)=219785kg m/s Momentum of m1 = m1 x Velocity = (m1x5.00)=67815kg m/s Momentum of m2 = m2 x Velocity = (m2x5.00)=151970kg m/s If velocity = Momentum/Mass = Momentum of m2/m2 = 151970/30394 = 5m/s which is true Momentum of M2 after the separation = m2 x v2 = 30394 x 0.96 = 29178.24kg m/s Any help much appreciated.