JEE Advanced · Physics · 28. Nuclear Physics
Half-life of a radio active substance ' \(A\) ' is 4 days. The probability that a nucleus will decay in two half-lives is
- A \(\frac{1}{4}\)
- B \(\frac{3}{4}\)
- C \(\frac{1}{2}\)
- D 1
Answer & Solution
Correct Answer
(B) \(\frac{3}{4}\)
Step-by-step Solution
Detailed explanation
After two half lives \(\frac{1}{4}\) th fraction of nuclei will remain undecayed. Or, \(\frac{3}{4}\) th fraction will decay. Hence, the probability that a nucleus decays in two half lives is \(\frac{3}{4}\).
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