It is often used on valuable artwork to confirm authenticity.
You might remember that it was mentioned earlier that the amount of carbon-14 in living things is the same as the atmosphere.Once they die, they stop taking in carbon-14, and the amount present starts to decrease at a constant half-life rate.Radiocarbon dating has been used extensively since its discovery.Examples of use include analyzing charcoal from prehistoric caves, ancient linen and wood, and mummified remains.However, once the organism dies, the amount of carbon-14 steadily decreases.
By measuring the amount of carbon-14 left in the organism, it's possible to work out how old it is.
The half-life is always the same regardless of how many nuclei you have left, and this very useful property lies at the heart of radiocarbon dating. The graph below shows the decay curve (you may recognize it as an exponential decay) and it shows the amount, or percent, of carbon-14 remaining.
You will notice that after around 40,000 years (or 8 half-lives), the amount left is starting to become very small, less than 1%.
Once the organism dies, the amount of carbon-14 reduces by the fixed half-life - or the time required for half of the original sample of radioactive nuclei to decay - of 5,730 years, and can be measured by scientists for up to 10 half-lives.
Measuring the amount of radioactive carbon-14 remaining makes it possible to work out how old the artifact is, whether it's a fossilized skeleton or a magnificent piece of artwork.
Free 5-day trial Ever wondered how scientists know the age of old bones in an ancient site or how old a scrap of linen is?