Physics · 2021
JEE Main · 3 August 2021, Shift 2 · Q18
A radioactive isotope has a half life of T years. After how much time is its activity reduced to 6.25 % of its original activity?
A radioactive isotope has a half life of T years. After how much time is its activity reduced to $\displaystyle 6.25 \%$ of its original activity ?
Official answer
(2)
$\displaystyle 4$ T years
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