Question

Many radioisotopes have important industrial, medical, research applications. One of these is 60Co which has a half-life of 5.2 yr and decays by the emission of a beta particle (energy 0.31 MeV) and two gamma photons (energies 1.17 MeV and 1.33 MeV). A scientist wishes to prepare a 60Co sealed source that will have an activity of at least 10 Ci after 30 months of use. (a) What minimum initial mass in milligrams (mg) of 60Co is required? (b) At what rate in milliwatts (mW) will the source emit energy after 30 months. (12 pts)

Answer 1