After one average life, what will be the ratio of number of undecayed nuclei to the number of decayed nuclei of a radioactive sample? [Take e = 2.7]
7:9
12:19
10:17
11:17
Mean life =tm=1λ
Required ratio =N0e−λtmN01−e−λtm=e−11−e−1
=1e−1=12.7−1=1017