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Estimate the age of the wood. The carbon in humans, and plants contains a small...
Estimate the age of the wood.
The carbon in humans, and plants contains a small percentage of the radioisotope Carbon-14, which has a half life of 5730 years. for example, a piece of wood taken from a cave dwelling in New Mexico has a C-14 content that is only 25% of that of wood cut today. Estimate the age of the wood.
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Elementary School Teacher
Half life of Carbon-14 = 5370 years
Percentage of Carbon-14 in cave wood as compared to Present day wood = 25%
Expected Age of Cave wood = (Ln(25%)/Ln(50%))*Half-Life
= 10740 years
Estimated age of cave wood = 10740 Years
Posted by najm1947 on February 2, 2012 at 3:37 PM (Answer #1)
If the orginal amount of carbon-14 in cave wood was X, then, you would have 1/2 X in 5370 years or one half-life. For the radioactive isotope to decay to 1/4 X, an additional half-life would have passed. This means that 10,740 years would have passed. Radioactive carbon dating is used for relatively recent items to date, as the half-life isn't as long as other radioactive elements. It is only used to date materials less than 62,000 years old. The C14 in organic compounds decays at a fixed rate of radioactive decay and fairly reliable dates can be attributed to archaelogical finds such as bones, clothing, etc.
Posted by trophyhunter1 on February 3, 2012 at 10:29 PM (Answer #2)
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