For an object to escape from the surface of a celestial body, the kinetic energy must be: __________?

1. Less than gravitational potential energy
2. Equal to gravitational potential energy
3. Greater than gravitational potential energy
4. None

Escape velocity (√(2GM/R)) depends on the planet’s mass (M) and radius (R), not the escaping object’s mass (m). Thus, a feather and a rocket require the same escape velocity from Earth, though achieving it demands vastly different energies.