Thursday, September 02, 2004

Electricity

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Article by Dave Barry
Source: http://www.comp.leeds.ac.uk/Perl/Misc/electricity.txt

Today's scientific question is: What in the world is electricity and
where does it go after it leaves the toaster?

Here is a simple experiment that will teach you an important
electrical lesson: On a cool dry day, scuff your feet along a carpet,
then reach your hand into a friend's mouth and touch one of his dental
fillings. Did you notice how your friend twitched violently and cried
out in pain? This teaches one that electricity can be a very powerful
force, but we must never use it to hurt others unless we need to learn
an important lesson about electricity.

It also illustrates how an electrical circuit works. When you scuffed
your feet, you picked up batches of "electrons", which are very small
objects that carpet manufacturers weave into carpet so that they will
attract dirt. The electrons travel through your bloodstream and
collect in your finger, where they form a spark that leaps to your
friend's filling, then travel down to his feet and back into the
carpet, thus completing the circuit.

AMAZING ELECTRONIC FACT: If you scuffed your feet long enough without
touching anything, you would build up so many electrons that your
finger would explode! But this is nothing to worry about unless you
have carpeting.

Although we modern persons tend to take our electric lights, radios,
mixers, etc. for granted, hundreds of years ago people did not have
any of these things, which is just as well because there was no place
to plug them in. Then along came the first Electrical Pioneer,
Benjamin Franklin, who flew a kite in a lightning storm and received a
serious electrical shock. This proved that lightning was powered by
the same force as carpets, but it also damaged Franklin's brain so
severely that he started speaking only in incomprehensible maxims,
such as, "A penny saved is a penny earned." Eventually he had to be
given a job running the post office.

After Franklin came a herd of Electrical Pioneers whose names have
become part of our electrical terminology: Myron Volt, Mary Louise
Amp, James Watt, Bob Transformer, etc. These pioneers conducted many
important electrical experiments. Among them, Galvani discovered
(this is the truth) that when he attached two different kinds of metal
to the leg of a frog, an electrical current developed and the frog's
leg kicked, even though it was no longer attached to the frog, which
was dead anyway. Galvani's discovery led to enormous advances in the
field of amphibian medicine. Today, skilled veterinary surgeons can
take a frog that has been seriously injured or killed, implant pieces
of metal in its muscles, and watch it hop back into the pond --
almost.

But the greatest Electrical Pioneer of them all was Thomas Edison, who
was a brilliant inventor despite the fact that he had little formal
education and lived in New Jersey. Edison's first major invention in
1877 was the phonograph, which could soon be found in thousands of
American homes, where it basically sat until 1923, when the record was
invented. But Edison's greatest achievement came in 1879 when he
invented the electric company. Edison's design was a brilliant
adaptation of the simple electrical circuit: the electric company
sends electricity through a wire to a customer, then immediately gets
the electricity back through another wire, then (this is the brilliant
part) sends it right back to the customer again.

This means that an electric company can sell a customer the same batch
of electricity thousands of times a day and never get caught, since
very few customers take the time to examine their electricity closely.
In fact, the last year any new electricity was generated was 1937.

Today, thanks to men like Edison and Franklin, and frogs like
Galvani's, we receive almost unlimited benefits from electricity. For
example, in the past decade scientists have developed the laser, an
electronic appliance so powerful that it can vaporize a bulldozer 2000
yards away, yet so precise that doctors can use it to perform delicate
operations to the human eyeball, provided they remember to change the
power setting from "Bulldozer" to "Eyeball."