A storage facility contains equal initial numbers of nuclei of two radioactive isotopes, A and B, that emit comparable radiation.
• Isotope A has a decay constant of 1.6×10−9s−1.
• Isotope B has a half-life of 11yr.
(a) Calculate the half-life of isotope A in years.
(b) Calculate the decay constant of isotope B in s−1.
(c) Rank isotopes A and B in order of nuclear stability, from most to least stable, and justify your ranking quantitatively.
(d) After 25years of storage, which isotope contributes the larger share of the remaining activity? Quantitatively compare their activities and explain the physical reason for the difference.