1. The problem statement, all variables and given/known data A projectile is fired vertically from Earth's surface with an initial speed of 3.1 km/s. Neglecting air drag, how far above the surface of Earth will it go? 2. Relevant equations KF+UF=KI+UF U=-G(M1m2)/r2 K=1/2mv2 mass of earth = 5.972E24 radius of earth = 6371km G=6.673E-11 3. The attempt at a solution 1/2mv2F+(-G(M1m2)/r2F=1/2mv20+(-G(M1m2)/r20 I can cancel the m because they're in every term so and final kinetic energy since it should be zero at max height. (-GM1)/r2F=1/2v20+(-GM1)/r20 Next I try and get the rF by itself (-GM1)=(1/2v20+(-GM1)/r20)*r2F (-GM1)/(1/2v20+(-GM1)/r20)=r2F √(-GM1)/(1/2v20+(-GM1)/r20)=rF then I subtract rF from the initial r0 to get my answer. Did I do this right?