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- Electricity
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- 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 us that electricity can be a very powerful force, but we must never
- use it to hurt others unless we need to learn an important electrical lesson.
- It also teaches us 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 -- where it sinks like a stone.
- 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 thousand 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."
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