| |
What
in the World is Electricity?
12-VIII-2002
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." |
|