The gravitational force between a H-atom and another particle of mass m will be given by Newton’s law:
F = \(G \frac{M.m}{r^2}\) where r is in km and
1
M = mproton + melectron.
2
M = mproton + melectron \(-\frac{B}{c^2}\) (B = 13.6 eV).
3
M is not related to the mass of the hydrogen atom.
4
M = mproton + melectron \(-\frac {|V|}{c^2}\) | V | = magnitude of the potential energy of electron in the H - atom).