1. The problem statement, all variables and given/known data 1.A rocket at the surface of the Earth is launched with a speed of 2500m/s. What is the orbit that the rocket will achieve? 2.A meteorite travelling at 3500m/s approaches Earth from outer space. With what speed will the meteorite hit the surface of Earth? 3.Also, in general does an object on the surface of Earth always have gravitational energy? If the problem doesn't state it's initial velocity, do I assume it has no kinetic energy initially on the surface of Earth? 2. Relevant equations Ek = 1/2mv^2 Eg = -Gmm/r Et = -Gmm/2r 3. The attempt at a solution My main question is the third question. Do objects in orbit always have Eg? Ek? Because if I can understand that, then I'll know if my answers are right or not. 1. 1/2mv^2 - Gmm/r = -Gmm/(r+r1) I believe the rocket will lose all it's kinetic energy at a point (slow down) and transferring all the energy to Eg. Solving for r1, I get about 3.36e5m 2. 1/2mv^2 - Gmm/r = 1/2mv^2 - Gmm/r1 Well, it is at a distance of r away from the planet before it travels towards Earth so it must have Eg right? Then when it returns to Earth's surface it will have an Eg of Gmm/r1, r1 is the earth's radius to center? But if this is right how do I know what is the initial distance?