T H E N I H C A T A L Y S T | J U L Y A U G U S T 2005 |
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CATALYTIC REACTIONS? If you have a photo or other graphic that reflects an aspect of life (including laboratory life) or a quotation that scientists mightappreciate that would be fit to print in the space to the right, why not send it to us via e-mail: <catalyst@nih.gov>; fax: 402-4303; or mail: Building 2, Room 2E26. Also, we
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Kids' Catalyst: Worth Its Weight in Gold Eureka: Part 1 One day about 2000 years ago, the Greek King Heiro wanted a new crown. So he weighed out some gold, gave it to his local crown-making craftsperson, and soon had a shiny new diadem. But something made King Heiro suspicious. Convinced he had been cheated out of some of his gold, he asked around for help on how to prove it. The problem eventually came to a very clever guy named Archimedes (youll hear his name many times again in your travels!). Bright as he was, this one had him stumped. How to prove the crown wasnt 100 percent gold? After days of contemplation, he finally took a break. What does a frustrated scientist do to relax? Take a bath. Archimedes stepped into his tub and the very same thing happened then as would happen now if you got into a tub full of water: It would overflow. So with water spilling all over the place, the solution to the problem hit him. He was so excited that he was crying "Eureka!" (Greek for "I have found it") out the door, through the streets, and to the king. (In his glee, he apparently forgot his robe, guaranteeing that this would be the stuff of legend!) So how did Archimedes figure it out? Heres what he knew: the weight of the crown and what the crown was allegedly made from. He placed the crown into a vessel full of water to see how much water overflowed. Then he did the same with the same amount weight-wise of gold. Even though the crown was the same weight as the gold, it displaced a different amount of water. The king had his proof, the crown maker got his just reward, and Archimedes put his robe on. Now you dont need gold crowns lying around to test the volume of irregularly shaped objects, and you certainly dont need anything more than a carefully-made scale to tell that two things shaped the same are made out of different materials. Next issue we will take a bunch of pennies and prove that not all pennies are created equal using a surprisingly accurate home scale. Maybe you can work on that problem in the meantime, but heres a hint: Compare U.S. pennies made before and after 1982. Youll be surprised!
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