JEE Mains · Physics · STD 12 - 13. Nuclei
The half life period of a radioactive substance is 60 days. The time taken for \(\frac{7}{8}\) th of its original mass to disintegrate will be \(......days\)
- A \(120\)
- B \(130\)
- C \(180\)
- D \(20\)
Answer & Solution
Correct Answer
(C) \(180\)
Step-by-step Solution
Detailed explanation
\(7 / 8\) disintegrates means \(1 / 8\) remains \(\operatorname{Or}\left(\frac{1}{2}\right)^{3}\) \(\therefore 3\) half lives \(=180\) days
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