1. Tardigrade
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  4. The activity of a radioactive sample is measured as 9750 counts per minute at t= 0 and as 975 counts per minute at t = 5 minutes. The decay constant is approximately

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Q. The activity of a radioactive sample is measured as 9750 counts per minute at t= 0 and as 975 counts per minute at t = 5 minutes. The decay constant is approximately

Atoms

Solution:

$A = A_0 \, e^{-\lambda t}$ or 975 = 9750 $e^{-\lambda \times 5}$ Hence $e^{5 \lambda} $ = 10 . That is $5 \lambda = log_e$ 10
= 2.3026 $log_{10}$ 10 = 2.3026 or $\lambda$ = 0.461