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How was the "I" in I=E/R derived? In other words, what does the "I" stand for (other than current).

The relationship I=E/R is an empirical physical law relating the Quantity of electrical charge, the difference in electrical potential, and the electrical resistance. The form of the relation is the same for the simple flow of a fluid in a straight pipe, where E becomes the pressure drop along the pipe, R is the flow resistance of the pipe, and the flow in the pipe is say liters/min and corresponds it the electrical resistance.

To get a feel for how much charge 1 coulomb is, consider that each and every one an Avagadro's number [6.023x10^23] of electrons carries 1.60217733x10^ -19 coulombs. I'll leave the number crunching.

Vince Calder

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