I've heard it said that any object that wants to escape another object's gravitational pull must travel at the object's escape velocity. I assume this is incorrect, and would only apply to something with an initial velocity at the escape velocity (like a bullet from a gun would need to travel at the Earth's escape velocity to not fall back to earth.) Is it correct that if it gradually exerts force like a space elevator then something could travel much slower than the escape velocity? 1) So as a typical space shuttle or rocket does not expend all of its fuel at launch, but releases it gradually; does that mean that the space shuttle travel's much slower than the Earth's escape velocity. 2) If a black hole is defined as an object with an escape velocity equal to the speed of light, why could something gradually exerting force (like a space elevator) not "climb" its way out of the black hole's gravitational pull?