The Tsiolkovsky rocket equation or ideal rocket equation is an equation used to calculate the impulse imparted by a rocket which other object ejecting mass, such as a hose. The equation is where ∆v is the change in velocity, ve is the velocity of the ejected material, mi is the initial mass and mf is the final mass. In a gravitational field, this becomes File:Rotating tube.png This mechanics-related article contains minimal information concerning its topic. You can help the Physics Wiki by adding to it.