Question

A fossil containing radioactive material has 25% of the original carbon-14 present. The half-life of carbon-14 is 5730 years. How old is the fossil?

Answer 1

Solution.

$t(1/2) = \frac{ln(2)}{k}$

$k = 1.21 \times 10^{-4} \ years^{-1}$

$k \times t = ln(\frac{100}{25})$

t = 11457 years

Answer:

t = 11457 years