AP EAMCET · PHYSICS · Nuclear Physics
Half-life of a radioactive substance is 18 minutes. The time interval between its \(20 \%\) decay and \(80 \%\) decay in minutes is
- A 6
- B 9
- C 18
- D 36
Answer & Solution
Correct Answer
(D) 36
Step-by-step Solution
Detailed explanation
After \(n\) half-life, the numbers of atom left undecayed is given by, \(\begin{aligned} & N=N_0\left(\frac{1}{2}\right)^n \\ & n=\frac{t}{T_{\frac{1}{2}}} \text { or } N=N_0\left(\frac{1}{2}\right)^{\frac{t}{T_{1 / 2}}} \end{aligned}\) For \(20 \%\) decay of radioactive…
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