How does the measure of radio-active elements help scientists calculate a fossils age?

Question

the title pretty much says it all. its for science. i cant find the answer. and people please help me. no nonsense

Answer 1

cutie,

Atoms of certain elements (called the "parent") break down over time and turn into a different element (called the "daughter"). Since the rate at which parent turns into daughter can be measured in lab experiments, we know how much parent and how much daughter should be in a sample at any given time.

So if you take a fossil and measure how much of the parent element it has and how much of the daughter element it has, you can calculate how much time has gone by and then you know the age of the fossil.

Answer 2

If you know the half life of something like carbon, then depending on how much is left then you can easily determine how old the carbon/other elements are in something