1. The problem statement, all variables and given/known data Calculate the final velocity of a rocket if the velocity of the ejected gas is c, initial mass of rocket is M0 and final mass is Mr, v0=0. 2. Relevant equations We have to calculate the final velocity of rocket. 3. The attempt at a solution Because the total momentum of an isolated system is conserved, the total system - rocket + exhausted gas - must still have zero momentum. If the velocity of gas is c, then: M0*v - (M0-m)*c=0 m - mass of gas ejected What to do next?