Because the cosmic ray bombardment is fairly constant, there’s a near-constant level of carbon-14 to carbon-12 ratio in Earth’s atmosphere.
Scientists call that time its "half-life."Living things constantly replenish the carbon in their bodies, animals from food, plants from the atmosphere, but after death, that process stops.
What methods do they use and how do these methods work?
In this article, we will examine the methods by which scientists use radioactivity to determine the age of objects, most notably carbon-14 dating.
Carbon-14 dating is a way of determining the age of certain archeological artifacts of a biological origin up to about 50,000 years old.
It is used in dating things such as bone, cloth, wood and plant fibers that were created in the relatively recent past by human activities.