What is the minimum energy required to lunch a satellite of mass m from the surface of a planet of mass M and radius R In a circular orbit at an altitude of 2R?
As we know, Gravitational potential energy = - GM /r
and orbital velocity, v0 = vGM/R+h
Ef = ½ mv20 – GMm/3R = ½ m GM/3R – GMm/3R
= GMm/3R (1/2-1) = - GMm/6R
Ei = - GM/R + K
Ei = Ef
Therefore minimum required energy, K = 5GMm/6R