Describe the process of carbon dating
The carbon dioxide is absorbed by plants, and the plants are eaten by animals, thus contaminating every living thing on earth with radioactive carbon. As time passes, the C14 in its tissues is converted back into nitrogen.If we know what the original ratios of C14 to C12 were in the organism when it died, and if we know that the sample has not been contaminated by contact with other carbon since its death, we should be able to calculate when it died by its C14 to C12 ratio.The ions produced are forced into a magnetic field where the different mass of the carbon isotopes causes a different deflection, allowing the quantity of each isotope to be measured.This method is claimed to be more accurate than the older and slower method of counting the number of radioactive decay emissions from a quite large sample.But in actual practice, we know neither the original ratios nor if the specimen has been contaminated and are forced to make what we hope are reasonable assumptions.The tiny initial amount of C14, the relatively rapid rate of decay (the half-life of C14 is currently about 5700 years) and the ease with which samples can become contaminated make radiocarbon dating results for samples "older" than about 50,000 years effectively meaningless.
Radiocarbon dating is frequently used to date ancient human settlements or tools. It is a stable atom that will not change its atomic mass under normal circumstances.They found large variations in the radiocarbon 'dates' of objects of known age sent to 38 radiocarbon 'dating' laboratories around the world.Thirty-one of the labs gave results that the British group called unsatisfactory.Radioactive carbon (Carbon 14) is formed in the upper atmosphere as a byproduct of cosmic radiation.Cosmic rays are positively charged atoms moving at enormous speeds.