of the Electrons in the Neon Atom. 341 



at the centre of the atom. Since these two inner electrons 

 are upon one of the axes of rotation, it follows that they only 



have two velocities, but this is sufficient to make th 

 mapped out by these electrons spherical in shape. 



shell 



Fig. 1, 



Y 



^9 



^ 



Z' 



X' 



Y' 



The next point that arises is with regard to the laws of 

 force holding between two electrons in the atom, and as 

 there is no experimental evidence to the contrary we imagine 

 that the inverse square law holds good. 



We are now in a position to calculate the forces~acting on 

 any electron in the outer shell. We shall resolve the forces 

 along the three perpendicular lines e x e s , e x e 2 , and e x e- r Since 

 the electron is to be in equilibrium under the forces present, 

 it follows that the total force acting along any one of the 

 three perpendicular lines must be zero, and so we obtain 

 three equations. 



Let us first take the forces acting along the line e x e B , and 



further let the positive direction be e\e%. The charge on the 

 electron is " e" Charge of nucleus = E = lCte. Mass of 

 electrons when moving with a small velocity = m. Angular 



