A vehicle with thrust less than 1G cannot lift off from Earth's surface due to the gravitational force acting downwards. However, once airborne, a vehicle can achieve escape velocity with any amount of thrust over time, as the gravitational pull decreases with altitude. The discussion highlights that escape velocity is a function of altitude, and for any given velocity, there exists a height where it exceeds escape velocity. The Falcon 9, for example, could theoretically escape Earth's gravity well if it maintains thrust over time, despite not achieving immediate escape velocity.
PREREQUISITESAerospace engineers, physics students, and enthusiasts interested in rocket science and the mechanics of space travel will benefit from this discussion.
