Question:medium

Half-life period of a radioactive substance is \(10\,\text{min}\). Then amount of substance decayed in \(40\,\text{min}\) will be:

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After \(n\) half-lives: remaining \(=\left(\frac{1}{2}\right)^n\), decayed \(=1-\left(\frac{1}{2}\right)^n\).

Updated On: Apr 16, 2026

\(25\%\)
\(50\%\)
\(75\%\)
None of these

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The Correct Option is D

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