# Radioactivity half life carbon dating dating now ep1

It is naturally produced in the atmosphere by cosmic rays (and also artificially by nuclear weapons), and continually decays via nuclear processes into stable nitrogen atoms.

Suppose we have a sample of a substance containing some *carbon*-14.

This fact is used in radiocarbon *dating* to determine the age of fossils up to \(60\ 000\) years old.

Roughly speaking, while an organism is alive, its interactions with its environment maintain a constant ratio of **carbon**-14 to **carbon**-12 in the organism; but after it dies, the **carbon**-14 is no longer replenished, and the ratio of **carbon**-14 to **carbon**-12 decays in a predictable way.

Though still heavily used, relative **dating** is now augmented by several modern **dating** techniques.

Radiocarbon **dating** involves determining the age of an ancient fossil or specimen by measuring its **carbon**-14 content.

Libby invented *carbon* *dating* for which he received the Nobel Prize in chemistry in 1960.

Until this century, relative *dating* was the only technique for identifying the age of a truly ancient object.

By examining the object's relation to layers of deposits in the area, and by comparing the object to others found at the site, archaeologists can estimate when the object arrived at the site.

Let \(m\) be the mass of **carbon**-14 in nanograms after \(t\) years.

satisfy the differential equation \[\dfrac = -0.000121 \, m.\] Suppose our sample initially contains 100 nanograms of *carbon*-14.