Physics · 2021
JEE Main · 27 August 2021, Shift 1 · Q19
There are 10^10 radioactive nuclei in a given radioactive element. Its half-life time is 1 minute. How many nuclei will remain after 30 seconds? (√ 2…
There are $\displaystyle 10^{10}$ radioactive nuclei in a given radioactive element. Its half-life time is $\displaystyle 1$ minute. How many nuclei will remain after $\displaystyle 30$ seconds ?
$$(\sqrt{2}=1.414)
$$
Official answer
(3)
$\displaystyle 7 \times 10^9$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.