Physics · 2015
JEE Main · 11 April 2015, Shift 1 · Q28
Let N_β be the number of β particles emitted by 1 gram of Na^24 radioactive nuclei (half life =15 hrs ) in 7.5 hours, N_β is close to (Avogadro…
Let $\displaystyle \mathrm{N}_\beta$ be the number of $\displaystyle \beta$ particles emitted by $\displaystyle 1$ gram of $\displaystyle \mathrm{Na}^{24}$ radioactive nuclei (half life $\displaystyle =15 \mathrm{hrs}$ ) in $\displaystyle 7.5$ hours, $\displaystyle \mathrm{N}_\beta$ is close to (Avogadro number $\displaystyle =6.023 \times 10^{23} / \mathrm{g}$. mole) :
Official answer
(2)
$\displaystyle 7.5 \times 10^{21}$
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JEE Main 2015 Physics question, with the answer from NTA’s final answer key. Where our answers come from.