On Mon, 25 Nov 2013 20:43:01 +0100, nestork wrote:

And what about this "ground," as mentioned above? The power company
essentially uses the earth as one of the wires in the power system. The
earth is a pretty good conductor and it is huge, so it makes a good
return path for electrons.

I'm glad you found that, because there MUST be a complete circuit for
current to flow (assuming an imbalance, as someone else noted).

The fact that the earth isn't obviously a "wire" is lost on some
people who simply assume earth is ground potential and that's that.

But, that's OK.

That's because *both* ways of thinking work just fine, simply because the
earth contains more electrons than anything on earth (which goes without
saying). It's like the car frame example. Exactly. Only on a huge scale.

So, both concepts work simply because earth and the car frame are special
things that don't look like wires, but, they act both like zero potential
and like wires.

Specifically, the earth is both a zero potential, and a huge conductor
back to the power company.

As Gallileo supposedly said on his deathbed to those who couldn't
fathom the wonders of the earth ... "and yet, it does".