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# Grounding electrodes

```This subject is getting quite interesting.  Really, it is, and I am enjoying
it a lot.  :-)  Truths, half truths, myths, erudite analysis, very
interesting insights, everything!! :-)

I do believe that grounding electrodes DO have one very useful property.
They will instantly trip your GFI if you have an even very slightly exposed
voltage source, and this will keep you and your charges very much alive.  I
heartily approve of keeping all of us alive.  :-)

As for the rest, I am not convinced by proper scientific evidence.  Lots of
anecdotal evidence, but the really good numbers stuff still has not shown up.
No double-blind experiments, no control groups, no Null Hyphothesis.  I
cannot prove you are wrong, but you have as yet failed to _prove_ the
_claimed_ benefits of the grounding probe.  Sorry, it just does not make
sense to me.  By the way, I have been a Ham Radio operator for about forty
years, and I have built a LOT of electronic gadgets, from receivers to
transmitters, power supplies, even meters, and such.  My mind is not closed
on this subject, but so far - I don't believe it.

Now, just for the fun of it - - - - According to Ohm's Law, E=I/R, the
practical effect of a current source through a tank of water is quite similar
to that which exists when an EMF (voltage) is, for example 100 volts applied
to the ends of a ten inch long resistor.  The voltage is not important, I
picked 100 volts because it is easy to figure.  We could have used 1000
volts, or perhaps 10 volts.  But, for now, I will stick to 100 volts.  The
value in ohms of the resistance of the resistor is immaterial to us.
(Actually, all the value of the resistance does is determine how much CURRENT
will flow through the resistor at 100 volts EMF.)  Yes, more voltage gives
more current, hence more power dissipated, hence more heat.   That is the
reason resistors all have a rated power dissipation number.  The number of
ohms of resistance is expressed on most of the small resistors you will find
in, for example, a transistor radio, with colored bands.  The different
colors translate into different numbers.  Some resistors also have the power
dissipation listed. Doesn't matter, we have picked a nice, easy ten inch long
resistor.  Easy to figure stuff out this way.

Any two points on this ten inch long resistor will have a voltage between
them equal to ten volts per inch.  Doesn't matter at all where you check that
old voltage, that ten inch long resistor is dropping voltage, ten volts per
inch.

If we have another resistor in the circuit, paralleling the first one, our
second resistor only five inches long, and half the resistance of the first
one, CURRENT WILL FLOW THROUGH BOTH RESISTORS AT THE SAME TIME. The amount of
the current can again be figured using Ohm's Law.  More current will flow
through the lower value resistor.

Thus, the actual VOLTAGE operating on our fish will depend upon how long the
fish is (or how thick, if he/she is swimming at right angles to the current),
not on where the fish is located along that path.  The fish will have a very
very low resistance, a lot lower than the water. (unless it is Sea water, and
in that case, all bets are off!  :-P ) Again, by Ohm's Law, the very low
resistance fish will now carry the lion's share of the current through
his/her hapless body. Now, if we remember just how tiny the electrical
impulses are, that the fish's brain is sending down the nerves to stimulate
the muscles of the fish so it can swim, we can see that our current may be
quite a nuisance for the fish.  A year or so ago, there was an article in one
of the big fish magazines in which this photographer was "shocking" the fish
so they would display their fins and be quite effectively frozen into
position for the photo.   It does not take much current to really mess up a
fish.

When lightning strikes the ground, it may be delivering possibly millions of
volts of energy, and hundreds of amperes of current.  (for a very short
time.) The voltage from that lightning bolt dissipates along the surfaced of
the earth just the same way the voltage is dissipated over our sample
resistor.  If standing on the earth within several hundred feet of the
strike, you might, therefor, have a voltage between one foot and the other of
a thousand or more volts.  You would get a very NASTY shock.  This has
happened to me, twice in my life.  You don't have to be "hit" by lightning to
BE "hit" by lightning.

The fish does not have to be "hit" by the current in the tank, but the fish
will become part of the circuit.  I have been "part of the circuit" more than
a few times.  As far as the laws of Physics is concerned, I guess I have been
a LIVE "grounding probe," and although my state of mind at the time certainly
was not calm and observant, I didn't notice that the fish appreciated my
contribution to grounding the tank.  :-D

Hey, we believe fantastic claims regarding foods.  We believe some very
esoteric stuff regarding intake and use of trace elements.  Guess it is
logical that many of us believe in grounding probes.  I just don't happen to
be one of those believers - except, as I have stated more than once on this
List, I do believe they sure do a great job of tripping a GFI.  :-)

I am not cynical, just suspicious of things that appear to violate the Laws
of Physics.  Especially things that just seem too good to be true.

Thanks, all.
```