Concept explainers
As we saw in Section 6.5, a radioactive substance decays exponentially: The mass at time t is m(t) = m(0)ekt, where m(0) is the initial mass and k is a negative constant. The mean life M of an atom in the substance is
For the radioactive carbon isotope, 14C, used in radiocarbon dating, the value of k is –0.000121. Find the mean life of a 14C atom.
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Chapter 7 Solutions
Single Variable Calculus
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