Question

Could anyone help?

Answer 1

When plants fix atmospheric carbon dioxide (CO2) into organic material during photosynthesis they incorporate a quantity of 14C that approximately matches the level of this isotope in the atmosphere (a small difference occurs because of isotope fractionation, but this is corrected after laboratory analysis[citation needed]). After plants die or they are consumed by other organisms (for example, by humans or other animals) the 14C fraction of this organic material declines at a fixed exponential rate due to the radioactive decay of 14C. Comparing the remaining 14C fraction of a sample to that expected from atmospheric 14C allows the age of the sample to be estimated.

http://en.wikipedia.org/wiki/Radiocarbon_dating

Answer 2

yep...the language is fine.. i just selected the portion where the exact explaination is given instead of just giving the link..

Answer 3

some atoms tend to break down into smaller atoms to gain stability of nucleus,the radioactive decay...C14 is one of them..it is transferred through plants to animals as described above..now after some time we can use this C14 present to determine the age...
rate of radioactive decomposition is proportional to the initial no. of parent nuclei present and there is an expression for this rate {it is an exponential function }...it involves two variables...we measure the rate of decomposition at two diff times and solve these equations to get time(age)...