Concept explainers
Radiocarbon dating has a similar exponential time relation to our circuits. A living object contains the same proportion of radioactive 14C as its surroundings, but after the object dies, it no longer acquires 14C. for which the radioactive isotopes decay into 12C. The relationship is given by
N = N0e −λt
where N0 is the concentration of 14C at time of death. N is the concentration at a given time after death, and λ is a constant. Given that the half-life of 14C is 5700 years (where N/N0 = 1/2). Determine (a) the value (and units!) of the constant λ; (b) the approximate age of an extraterrestrial alien fossil discovered that has 16 g of 14C. and expected initial concentration of 42 g.
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