Engineering Board Exam Reviewer · Physics · hard
A fossil contains 25% of the carbon-14 found in living organisms. If the half-life of C-14 is 5730 years, how old is the fossil?
- 11460 years
- 1433 years
- 17190 years
- 5730 years
Answer
A. 11460 years
Solution
25% = (1/2)2 2 half-lives = 2(5730) = 11460 years.
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