A radioactive sample decays to th of its original quantity in 15 minutes. The half-life of the sample is
- (A)5 min✓ Correct
- (B)7.5 min
- (C)15 min
- (D)30 min
Answer: (A)
Solution
A sample left with one-eighth of its original amount has halved repeatedly until , which requires since . These three half-lives together take up the given 15 minutes, so each half-life lasts minutes.
JEE Main · 2022 · 28 Jul 2022 · Shift 2 · Single correct option