On all about circuits I keep seeing E in tables like this:
In the table I and R make sense with the units. But the E doesn't. So where does it come from?
I was looking at this article on superposition theorem..
"E" stands for "Electromotive force", which is essentially just voltage. We just have come used to using "V" instead of "E"
It would be the same as asking why Current is "I" even though it is measured as Amps.
Likewise it would also be the same as asking why Resistance is "R" even though it is measured in ohms.
This might also help you understand the saying "Eli the Ice Man" where the E stands for voltage.
The E is just a variable chosen by the author's preference of conventions, but it most likely derives from "Electro Motive Force" which is essentially synonymous with voltage.