A piece of charcoal used for cooking is found at the remains of an ancient campsite. a 0.94 kg sample of carbon from the wood has an activity of 1580 decays per minute. find the age of the charcoal. living material has an activity of 15 decays/minute per gram of carbon present and the half-life of 14c is 5730 y. answer
∴, activity = decay rate / mass = 1580/0.00094 = 1.681 X 10^6 decays per min per gram
Using the half-life formula, we have: activity of sample / activity of modern carbon = (1/2)^(age / half-life) ∴, Age = half-life x log (base 2) (modern activity / coal activity) = 5730 x log(base 2)(1.681X10^6/ 15) = 96115 years.
