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Question
A radioactive substance disintegrates into two types of daughter nuclei, one type with disintegration constant λ1 and the other type with disintegration constant λ2 . Determine the half-life of the radioactive substance.
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Solution
\[\ce{X ->[\lambda_{1}]D_1}\]
\[\ce{X ->[\lambda_{2}]D_2}\]
`lambda_"effective" = lambda_1 + lambda_2`
half life `(t_(1/2)) = ("In" 2)/(lambda_"effective") = (0.693)/(lambda_1+lambda_2`
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