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ussrasu
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Q: A 50-g chunk of charcoal is found in the buried remains of an ancient city destroyed by invaders. The carbon-14 activity of the sample is 200 decays/min. Roughly when was the city destroyed?
A: I used R = Ro*e^(-lambda*t) and t1/2 = ln2/lambda
t1/2 = 3.834*10^-12 s-1
and 200 decays/min = 3.33 decays/sec or 3.33 Bq
What is the initial acitivity/kg (Ro)?
The final acitivty/kg = 3.33 Bq/0.05 Kg = 66.66 Bq/Kg
Therefore R/Ro = 66.66/255
I then found the time to be 11 088 years
Can someone please check over this and see if this looks correct and advise of any corrections?
Many thanks!
A: I used R = Ro*e^(-lambda*t) and t1/2 = ln2/lambda
t1/2 = 3.834*10^-12 s-1
and 200 decays/min = 3.33 decays/sec or 3.33 Bq
What is the initial acitivity/kg (Ro)?
The final acitivty/kg = 3.33 Bq/0.05 Kg = 66.66 Bq/Kg
Therefore R/Ro = 66.66/255
I then found the time to be 11 088 years
Can someone please check over this and see if this looks correct and advise of any corrections?
Many thanks!