The specific impulse of a rocket engine is $3000 \mathrm{Ns} / \mathrm{kg}$. The mass of the rocket at burnout is $1000 \mathrm{~kg}$. The propellant consumed in the process is $720 \mathrm{~kg}$. Assume all factors contributing to velocity loss to be negligible. The change in vehicle velocity $\Delta u$ is____________ $\mathrm{km} / \mathrm{s}$ (round
off to 2 decimal places).
The specific impulse of a rocket engine is $3000 \mathrm{Ns} / \mathrm{kg}$. The mass of the rocket at burnout is $1000 \mathrm{~kg}$. The propellant consumed in the process is $720 \mathrm{~kg}$. Assume all factors contributing to velocity loss to be negligible. The change in vehicle velocity $\Delta u$ is____________ $\mathrm{km} / \mathrm{s}$ (round
off to 2 decimal places).