Read the following paragraph and answer the questions given below:
The quantity of
14C as well as that of
14CO
2 present in the atmosphere remains constant. The concentration of
14C in all living organisms remains almost constant during their life time. After their death,
14C is not taken up by them but the content of
14C assimilated begins to decay by emitting p-particles, with half-life period of 5568 years. The decay rate at the time of death of plant is 16.1 counts per minute per gram of carbon. Hence, by measuring the decay rate of the dead matter, the age of matter can be calculated, e.g. if decay rate of sample of wood is found to be N disintegrations per minute per gram of carbon after t years, then
where
= disintegration constant and N
0 = number of disintegrations per minute per gram when the plant had just died.
1.
14C is present in environment because of
