Tool/Calculator to compute the half-life, the radioactive period, the activity or the age of a radioactive element from its data / measurements for dating or radioactivity estimates.
Radioactivity Calculator - dCode
Tag(s) : Physics-Chemistry
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Radioactivity Calculator
Half-Life Calculator
Age Calculator
Activity Calculator
Answers to Questions (FAQ)
How to calculate the age of a radioactive material?
From its half-life $ \lambda $ (in years) and its current measured radiometric activity $ a $ (in percent), the age $ t $ of the radioactive material is calculated according to the formula:
$$ t = \frac{\lambda}{\ln(2)}\ln\frac{100}{a} $$
Example: $ a = 25\% $, $ \lambda = 1000 $ so $ t = 2000 $ years
How to calculate the half-life of a radioactive material?
From its age $ t $ (in years) and its current measured radiometric activity $ a $ (in percent), the half-life of a radioactive material $ \lambda $ (in years) is calculated with the formula:
$$ \lambda = \frac{t \ln(2)}{\ln\frac{100}{a}} $$
How to calculate the activity of a material?
From its age $ t $ (in years), and its half-life $ \lambda $ (in years), the activity of a radioactive material $ a $ (in percent) is calculated by the formula:
$$ a = \frac{100}{\exp(\frac{t \ln(2)}{\lambda})} $$
What is the radioactive period?
The radioactive period is the time necessary for half of the atoms of a radioactive isotope to decay naturally. The term half-life is a synonym for radioactive period.
What is radiometric dating?
Radiometric dating is the technique using a radioactive isotope present in a material (generally Carbon in carbon 14 dating) to determine the age of a material (several hundred or thousand years old) via the calculations above.
For shorter durations (decades), and recent materials, tritium dating is used. Tritium has been present in large numbers on Earth since nuclear tests.
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