Escape Velocity
The minimum speed required for a ballistic object to escape a massive body's gravitational field without further propulsion.
Governing formula
v_esc = √(2 G M / R)
SI unit
m/s
In depth
At escape velocity, total mechanical energy (KE + PE) equals zero. For Earth, escape velocity is approximately 11.2 km/s (~25,000 mph).
Examples in the real world
Interplanetary space probes launching from Earth needing to achieve 11.2 km/s to break free of Earth's gravity.