Carbon-14 dating reveals an artifact is 11,460 years old. Knowing its half-life is 5,730 years, how many half-lives have passed, and what fraction of original carbon-14 remains?

Mon, 04 May 2026 03:42:01 +0000

**Carbon-14 dating reveals an artifact is 11,460 years old. Knowing its half-life is 5,730 years, how many half-lives have passed, and what fraction of original carbon-14 remains?** Recent interest among researchers and history enthusiasts centers on carbon-14 dating reveals an artifact is 11,460 years old. With a half-life of 5,730 years, this age marks one key moment in understanding early human activity in the Americas. Knowing only the age and half-life, it’s natural to wonder: how many full half-lives have passed, and what remains of the original carbon-14? Carbon-14 dating relies on the predictable decay of carbon-14 isotopes. Each half-life—approximately 5,730 years—bleaches about half the remaining carbon-14. With an artifact dated to 11,460 years, the calculation becomes straightforward: divide 11,460 by the half-life of 5,730. That ratio equals exactly two half-lives. This means two full cycles have passed, allowing a clear, precise estimate of the remaining carbon-14. Using this rule:
11,460 ÷ 5,730 = 2 half-lives
After one half-life, 50% remains
After two half-lives, 25% of the original carbon-14 remains.