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Question
A piece of wood from the ruins of an ancient building was found to have a 14C activity of 12 disintegrations per minute per gram of its carbon content. The 14C activity of the living wood is 16 disintegrations per minute per gram. How long ago did the tree, from which the wooden sample came, die? Given half-life of 14C is 5760 years.
Solution
`t = 1/λ` In `R_0/R`
= `5760/0.693` In `16/12 = 5760/0.693` In `4/3`
= `5760/0.693 xx 2.303 log 4/3`
= 2391.12 years.
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