Answer to Question #240490 in Atomic and Nuclear Physics for hassan ihtisham

Question

Find the probability that the nucleus of 87Ra221 undergoes decay after three half-lives, if its a radioactive substance which has a half-life of 6 days. A. 1/6

B. 3/2 C. 5/6

D. 12

Answer 1

The correct answer is (c) 5/6

Best explanation: After one-half life, N₀/2 sample remains and N₀/2 decays.

After three half-lives, N₀/6 sample remains and 5N₀ /6 decays.

Hence the probability that a nucleus undergoes decay after two half-lives is 5/6