Original kilogram losing mass, status, scientists say
The squat metal cylinder weighs exactly 1 kilogram, as it should. It is the world's definition of mass, the standard kilogram against which all others are judged. Once the scientists know how many atoms are in 1 kilogram, that number could redefine the kilogram standard. The apparatus works by...
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Published in | Knight Ridder Tribune News Service p. 1 |
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Main Author | |
Format | Newsletter |
Language | English |
Published |
Washington
Tribune Content Agency LLC
22.11.2002
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Subjects | |
Online Access | Get full text |
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Summary: | The squat metal cylinder weighs exactly 1 kilogram, as it should. It is the world's definition of mass, the standard kilogram against which all others are judged. Once the scientists know how many atoms are in 1 kilogram, that number could redefine the kilogram standard. The apparatus works by balancing the force of gravity pulling down on a 1-kilogram mass against an upward-pulling magnetic force. The device can indirectly define the kilogram because all the other units measured -- such as time, length, voltage and resistance -- are already precisely defined. |
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