Physics · 2021
JEE Main · 25 July 2021, Shift 1 · Q1
The half-life of ^198 Au is 3 days. If atomic weight of ^198 Au is 198 g / mol then the activity of 2 mg of ^198 Au is [in disintegration/ second]:
The half-life of $\displaystyle { }^{198} \mathrm{Au}$ is $\displaystyle 3$ days. If atomic weight of $\displaystyle { }^{198} \mathrm{Au}$ is $\displaystyle 198 \mathrm{~g} / \mathrm{mol}$ then the activity of $\displaystyle 2$ mg of $\displaystyle { }^{198} \mathrm{Au}$ is [in disintegration/ second]:
Official answer
(1)
$\displaystyle 16.18 \times 10^{12}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.