Spherical anodes, grounding resistance

With a spherical-shaped anode of radius, r, which is immersed very deep in an electrolyte t > Kq), the current radiates uniformly outward in all directions. Between this spherical anode and the infinitely large and distant remote ground, a voltage U is applied which involves a current 7 = UIR. R is the grounding resistance. 

For a = b - d this gives the grounding resistance of the spherical anode according to Eq. (24-8) and for a = d and b 0 it gives the formula for the grounding resistance of a circular plate ground in full space ... 

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