Before radiometric dating (or other methods of absolute dating like counting tree rings) it was difficult to determine the actual age of an object.
Radiometric dating, based on known rates of decay of radioactive isotopes in objects, allows a specific age of an object to be determined to some degree of accuracy.
There is some ambiguity in the block diagram, so students must determine numerical ages for samples from the block diagram to test their relative age hypotheses.
Students "date" samples from the block diagram by counting the number of 235U and 207Pb atoms (colored beads) in a zircon (Ziploc bag).
Relative dating cannot tell us how long ago something took place, only that is followed one event and preceded another.
Geologists often need to know the age of material that they find.These use radioactive minerals in rocks as geological clocks.The atoms of some chemical elements have different forms, called isotopes.Short Answer: The term relative dating is distinguished from absolute dating to make it clear that one does not get a specific estimate of the age of an object from relative dating, but one does get such an estimate of true age from absolute dating.There are several techniques employed in both sets of methods. Long Answer: Sciences such as geology, paleontology and archeology are very interested in identifying the age of objects found and these scientists sometimes use both relative dating or absolute dating to characterize the age of the objects they study.