Interaction Forces of Two Conducting Spherical Drops

Comparison with the results of numerical calculations of Ei by means of exact formulae, Eq. (12.30), has shown that discrepancies between the values of E obtained and the respective values of Ei do not exceed 2% in the region A 0.1, and 

Forces F and F2, acting on the first and second particles bearing charges qi and qi, are connected by the obvious relationship  

Therefore, determination of one of the forces, for example E2, is sufficient for our purposes. 

From the definition of Maxwellian stress tension [91], it follows that projection of the force acting on particle 2 in the direction of a unit vector p is equal to  

Taking for p the unit vectors Ci and 62 in the direction of axes OZ and OH and using the properties ei n = z, 62 n = n and expressions for projections of the external normal n in a bispherical system of coordinates  

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