Suppose a projectile is fired upward from the surface of the Earth. If the initial speed of the projectile is v = 12.0 km/s (more than the escape velocity): how fast will it be moving it is so far from Earth that the force of gravity is approximately zero? The equation I was given to solve is: 1/2 v(initial)^2 - G(Mass of Earth) / radius of Earth = 1/2v(final)^2 I do NOT think this equation is correct. Can someone please help/advise? Many thanks.