Here is the problem. The only help I need with this is to determine the SPECIFIC type of defferential equations to use. (if any at all) i.e, 1st ODE's, ect. A rocket starts from rest on a ramp. Its propellant is consumed at a constant rate for a certain time. The propellent burns out after a certain time. Now the rocket is a projectile. It will land due to gravity at a certain D (distance) from ramp.