Formula for carbon 14 dating
Over time, carbon-14 decays radioactively and turns into nitrogen.
A living organism takes in both carbon-12 and carbon-14 from the environment in the same relative proportion that they existed naturally.
They have their work cut out for them, however, because radiocarbon (C-14) dating is one of the most reliable of all the radiometric dating methods.
The creationists who quote Kieth and Anderson never tell you this, however.
Question: A sample that is more than fifty thousand years old shouldn't have any measurable C-14. Radiocarbon dating doesn't work well on objects much older than twenty thousand years, because such objects have so little C-14 left that their beta radiation is swamped out by the background radiation of cosmic rays and potassium-40 (K-40) decay. this isotope [K-40] accounts for a large part of the normal background radiation that can be detected on the earth's surface" (p. This radiation cannot be totally eliminated from the laboratory, so one could probably get a "radiocarbon" date of fifty thousand years from a pure carbon-free piece of tin.
When a plant or animal dies it stops taking in carbon-14 and radioactive decay begins to decrease the amount of carbon-14 in the tissues.
The age of the plant or animal specimen containing carbon, such as wood, bones, plant remains, is determined by measuring the ratio of carbon-12 to carbon-14. Because of this relatively short half-life, carbon-14 can only be used to date specimens up to about 45,000 years old.
Carbon-14 has a half life of 5730 years, meaning that 5730 years after an organism dies, half of its carbon-14 atoms have decayed to nitrogen atoms.