Engineering Board Exam Reviewer · Applications: Growth and Decay · medium
The carbon-14 in a fossil is 30% of the amount in living tissue. If the half-life of carbon-14 is 5730 years, how old is the fossil?
- 2949 years
- 9953 years
- 4011 years
- 17190 years
Answer
B. 9953 years
Solution
A=A0e-kt with k= 2/5730. Setting A/A0=0.3: t= (1/0.3)/k=5730 (1/0.3)/ 2 9953 years.
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