Hi guys, how can a spaceship supposedly have zero Kinetic energy at escape speed? If this is the case, then once it has reached the area to escape the gravitational attraction of earth (till it is very minimal) is it saying that it has zero speed? Wouldn't it start falling back because it is just exactly at the threshold of the "escape area"? Then the spaceship can be said not able to escape earth right? What I am trying to say is that if this is the case, the kinetic energy of the spaceship shouldn't be zero ultimately right? By the way, my textbook says its zero. I don't know why lol. Thanks a lot people!!!