PHY 1120 Homework 13 Nuclear Physics and Radioactivity 1. A pi meson subatomic particle has a mass of 139 MeV/c2. What is this mass in unified atomic mass units (u)? 2. Use the figure provided to estimate the total binding energy of o4 Kr. 36 Binding energy per nucleon (MeV) 0 50 100 150 200 250 Number of nucleons, A (mass number) 3. Calculate the total binding energy (in MeV) and the binding energy per nucleon for ; Li The mass of a proton bound in a nucleus with an electron is an H atom (get mass for this and for a neutron from attached table). The mass ofg Liis 7.016003. 4. Calculate the energy released (in MeV) when tritium, 2 H decays by ~ emission. i H has a mass of 3.016049 u. 3 He has a mass of 3.016029 u. 5. How much energy (in MeV) is released in electron capture by beryllium, Z Be. Z Be has mass 7.016929 u. ; Li has mass 7.016003 u. 6. 15254 Cs has a half-life of 30.8 seconds. a) If we have 9.7 ug of Cs initially, how many Cs nuclei are present initially? b) How many Cs nuclei are present 2.9 minutes later? c) What is the \"activity\" (decay/time) at this time (2.9 minutes after initial conditions)