06-08-2006, 06:07 AM
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#1465 (permalink)
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My home? Discabled,
Join Date: Jun 2005
Location: Bristol, UK
Posts: 204
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http://science.howstuffworks.com/carbon-142.htm
Quote:
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Because the half-life of carbon-14 is 5,700 years, it is only reliable for dating objects up to about 60,000 years old. However, the principle of carbon-14 dating applies to other isotopes as well. Potassium-40 is another radioactive element naturally found in your body and has a half-life of 1.3 billion years. Other useful radioisotopes for radioactive dating include Uranium -235 (half-life = 704 million years), Uranium -238 (half-life = 4.5 billion years), Thorium-232 (half-life = 14 billion years) and Rubidium-87 (half-life = 49 billion years).
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Vita brevis,
Occasio praeceps |
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