Nuclear Physics

• The activity of a radioactive source is the number of particles that decay per unit time.
• Binding energy is the energy required to completely separate a nucleus into its separate constituents
• Mass defect is the difference between the mass of a completely separated nucleus, and the nucleus itself.
• Binding energy per nucleon is the minimum energy required to remove a nucleon from the nucleus
• Nuclear fusion occurs when two lighter nuclei combine to form one heavier nucleus
• Nuclear fission occurs when a heavier nucleus splits to form two lighter nuclei
• Components of a nuclear reactor:

  • Fuel rods: contain the uranium fuel
  • Control rods: made of born, used to slow down neutrons to control the rate of nuclear reaction. They are inserted in a certain way such that one neutron from a previous reaction will cause further fission. This keeps the power output constant.
  • Moderator: slows down fast moving neutrons to create thermal neutrons (slower). Water/heavy water are examples of moderators.
• Nuclear fusion requires very high temperature and pressure. This is to overcome the electrostatic forces of repulsion.