Compare and contrast relative and absolute dating
Overtime, the C-14 atoms give off radiation, and, eventually, transform into nitrogen-14 atoms.
The term used to define the amount of time it takes for half of the radioactive atoms, such as C-14, in a body or object to decay fully is known as a "half-life." The half-life of C-14 is approximately 5 730 years.
Unfortunately, though, it is impossible to determine exactly what the age of a fossil or artifact is using it. Well, many sources state that a recent test on the accuracy of C-14 dating - and thus, in turn, radioactive dating - attempted to date living penguins. Aside from these alleged inconsistencies, there is also the assumption that the decay rates of the isotopes is constant, or fixed.
While questionable, it appears as though the living penguins were dated as 8000 years old. If this were not the case, and the decay rate was susceptible to change or was not constant, it would render all ages inaccurate.
Much in the same way used to approximate the age of organic fossils, scientists use uranium-238's decay rate and the uranium-238 to lead-206 (which it decays into) ratio to approximate an age to assign to the object.
As can be seen, radioactive dating is quite an advanced and sophisticated technique.
Relative dating is used commonly when looking at the relative order of geological events.
A scientist may present a fossil's position or location in the strata accurately, but then interpret it as only a few thousand years old, whereas another may present it as many millions of years old. However, it must be noted that radiometric dating seems to emerge as superior. Even though it is fallible, and a small chance holds that it may even be entirely inaccurate, radiometric dating relies more on fixed or solid variables and factors than relative dating does, thus having a smaller margin for error.By using the known decay rate of C-14 as a reference and working out how much of the fossil's composition consists of C-14 and how much of it consists of N-14, they can approximate the age.But what about inorganic objects, such as, say, stone tablets, or rocks?An absolute age is one determined usually by mass-spectrometry where an isotope is measured and then an age can be calculated (a very very basic explanation).So in the end you can say this fossil is 50 thousand years old (always with an associated uncertainty).