Consider a rocket (initial mass m)o) accelerating from rest in free space. At first, as it speeds up its momentum p increases, but as its mass m decreases p eventually begins to decrease. For what value of m is p maximum? So I started out with the rocket equation which is m*v' = m'*v_ex + F_ext where, v_ex - exhaust speed F_ex = external force since it is accelerating the external force is -mg. I know that the momentum P(t) = mv. So in order to show for what value of m is P maximum, then do I simply solve for v(t) and let t go to infinity?