\(F_a=-\cfrac { n_{ e }q^{ 2 } }{ 4\varepsilon _{ o } } \cfrac { r-r_e }{ \left\{ (2a_{ e })^{ 2 }+(r-r_e)^{ 2 } \right\} ^{ 3/2 } } d\,r\)
is provided below.
It is both repulsive (positive) and attractive (negative) depending on the value of \(r_e\). A most interesting force.
