I learnt that the escape velocity is given by $$v_e = \sqrt{\frac{2GM}{r}}$$
Say I want to launch a rocket from the earth into space and want to calculate the escape velocity $v_e$ (I guess without air resistance). Which value of $r$ do I have to use:
- The mean radius of the earth...
- ... or the distance between the center of mass of the earth and the launch location?
Thanks in advance.
(I have basic classical (and quantum) mechanics knowledge, but I am very new to orbital mechanics.)