Question 287: Atoms & Nuclei

Question

Starting with a sample of pure ${}^{66}Cu,{7 \over 8}$ of it decays into $Zn$ in $15$ minutes. The corresponding half life is

Accepted Answer

${7 \over 8}$ of $Cu$ decays in $15$ minutes.
$	herefore$ $Cu$ undecayed $ = N = 1 - {7 \over 8} = {1 \over 8} = {\left( {{1 \over 2}} ight)^3}$
$	herefore$ No. of half lifes $=3$
$n = {t \over T}$ or $3 = {{15} \over T}$
$ \Rightarrow T = $ half life  period $ = {{15} \over 3} = 5\,\,$ minutes

Answer

$15$ minutes

Answer

$10$ minutes

Answer

$7{1 \over 2}$ minutes

Answer

$5$ minutes

Atoms & Nuclei

Starting with a sample of pure {}^{66}Cu,{7 \over 8} of it decays into Zn in 15 minutes. The corresponding half life is

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