JEE Mains · Physics · STD 12 - 13. Nuclei
The half-life of a radioactive substance is \(T\). The time taken, for disintegrating \(\frac{7}{8}\) th part of its original mass will be
- A \(3T\)
- B \(8T\)
- C \(T\)
- D \(2T\)
Answer & Solution
Correct Answer
(A) \(3T\)
Step-by-step Solution
Detailed explanation
\(t _{1 / 2}= T\) \(1 \underset{ T }{\longrightarrow} \frac{ T }{2} \underset{ T }{\longrightarrow} \frac{1}{4} \underset{ T }{\longrightarrow} \frac{1}{8}\) \(t _{7 / 8}=3 T\)
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