TS EAMCET · Physics · Nuclear Physics
The half-life of a radiocative isotope is \(30 \mathrm{~h}\). How long will it take to get reduced to \(12.5 \%\) of its initial amount?
- A 120 h
- B 90 h
- C 60 h
- D 50 h
Answer & Solution
Correct Answer
(B) 90 h
Step-by-step Solution
Detailed explanation
Half-life of radioactive isotope, \(T_{1 / 2}=30 \mathrm{~h}\) If \(N_0\) be the initial amount of radioactive isotope, then remaining amount \((N)\) in time \(t\) is given as \(N=125 \% \text { of } N_0=\frac{125}{100} \times N_0 \Rightarrow N=\frac{N_0}{8}\) We know that,…
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