1. The problem statement, all variables and given/known data Find: The minimum initial velocity at which a projectile should be shot vertically from the surface of the Earth so that it does not fall back to Earth. Note: This requires that v=0 as y approaches infinity. 2. Relevant equations a = -g[(R^2)/((R+y)^2)] g = 9.81 m/s^2 R = 6356 km (6.356E6 m) 3. The attempt at a solution My thought process is to substitute dv/dt for a and integrate to get to velocity, but it seems like I want to find velocity as a function of position? I am stuck, it is the acceleration as a function of position that is confusing me.