Escape Velocity

Escape velocity from the Earth

If M = MEarth and r = rEarth then vescape = m/s vescape =km/hr vescape =mi/hr. This data corresponds to a surface gravitational acceleration of g = m/s2 g = gEarth.

Orbit Velocity and Escape Velocity

If the kinetic energy of an object m₁ launched from the a planet of mass M₂ were equal in magnitude to the potential energy, then in the absence of friction resistance it could escape from the planet. The escape velocity is given by

To find the orbit velocity for a circular orbit, you can set the gravitational force equal to the required centripetal force.

Note that the orbit velocity and the escape velocity from that radius are related by