JEE Mains · Physics · STD 12 - 13. Nuclei
A radio-active material is reduced to \(1 / 8\) of its original amount in \(3\) days. If \(8 \times 10^{-3}\,kg\) of the material is left after \(5\) days. The initial amount of the material is \(.......\,g\)
- A \(64\)
- B \(40\)
- C \(32\)
- D \(256\)
Answer & Solution
Correct Answer
(D) \(256\)
Step-by-step Solution
Detailed explanation
\(N = N _0\left(\frac{1}{2}\right)^{ n }\) \(\frac{ N _0}{8}= N _0\left(\frac{1}{2}\right)^{ n }\) \(n =3\) \(3 \text { half lives }=3 \text { days }\) \(1 \text { half life }=1 \text { day }\) \(5 \text { days }=5 \text { half life }\) \(N = N _0\left(\frac{1}{2}\right)^{ n }\)…
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