Let us model the Helium atom, at time t=0, as (a) two electrons at x=-re and x=re, (b) two protons at x=-rp and x=rp (with rp<<re), and (c) two neutrons at z=rn and z=-rn. The diametrically opposed electrons are orbiting in a common circular orbit of radius re, at a common speed ve. re and ve are to be determined.
For brevity we write 1/4πε0 as k:
k=1/4πε0. (1)
Then the net Coulomb force on each electron has the magnitude
Fcoulomb=k2e2/re2-ke2/4re2 (2)
=7ke2/4re2.
There is also a Newtonian force on each electron:
Fnewton=mve2/re. (3)
Equating the Coulombic and Newtonian forces produces
mve2=7ke2/4re (4)
or
ve2re=7ke2/4m. (5)
By deBroglie each electron is associated with a wavelength λ:
λ=h/mve. (6)
In the ground state we assume that one of these wavelengths fits into the electron orbital:
λ=2πre. (7)
This being the case,
h/mve=2πre, (8)
and
vere=h/2πm. (9)
Dividing Eq. 5 by Eq. 9 produces
ve=7πke2/2h. (10)
Solving for re and ve:
re=.3024e-10, (11)
ve=3828460. (12)
Eq. 11 agrees well with the Internet value of .31e-10.