Monday, May 19, 2008

Q) A piece of hair shows the 14C activity falling by 75% of the initial activity. Given that 14C has half life of 5760 yrs, the age of the hair is ?

A)
Activity is proportional to amount of nuclei.
If activity falls by 75% it means nuclei decreased by 75%
means 25% left
means 2 half lives......(because after first half life, 50%remains, and after next half life half of that)
= 2 x 5760
= 11520 years


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