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A piece of ancient wood shows an activit...

A piece of ancient wood shows an activity of 3.9 disintegrations per second per gram of `""^(14)C`. Calculate the age of the wood. `T_(1//2)` of `""^(14)C=5568` years. Activity of fresh `""^(14)C=15.6` disintegrations/s/gram.

Text Solution

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`lamdaN=3.9`
`lamdaN_(0)=15.6`
`N/N_(0)=3.9/15.6=1/4=e^(-lamdat)`
`e^(lamdat)=N/N_(0)=4`
`lamdat=log_(e)4`
= `2.303xxlog_(10)4`
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