PHY 101 - Meeting #11


Topic(s) The Nucleus and Nuclear Energy
Reading List Pages 524-547 and 548-572
Objectives
  • Recall that Becquerel accidentally discovered radioactivity manifested by properties similar to x-rays
  • Know that the element uranium was responsible for Becquerel's radioactivity
  • Know that the nucleus of an atom consists of protons and neutrons which together are known as nucleons
  • Know what is meant by atomic number and mass number
  • Be able to understand the A-Z notation used to describe an element (i.e. 4He2 or the other variations)
  • Understand the meaning of the term isotope
  • Be able to name and describe the isotopes of hydrogen
  • Be able to identify and discuss the three types of radiation mentioned in your text, a, b and g
  • Understand that alpha particles are helium atoms without the electrons, beta particles are equal in mass to electrons and can be either positively or negatively charged
  • Know that gamma radiation is a very high energy photon
  • Know that nuclear decays can be described in terms of nuclear reactions that conserve electrical charge and nucleon number
  • Know what it means to say that one element transmutes into another
  • Know how much the nucleon number changes for a, b+, b- and g decay
  • Be able to compete nuclear decay reactions similar to those in the book
  • Understand that each radioactive nucleus has a certain probability of decaying in the next second - no matter how long it may have already "lived"
  • Know what is meant by the term half-life, and be able to solve simple problems that involve it
  • Recall that carbon-14 is used to date previously living artifacts
  • Know the penetration powers of a, b and g radiation as well as the harm that each can do to living tissue
  • Be familiar with the naturally occuring and man made sources of radioactivity. 
  • Recall that natural radiation exceeds man made by a factor of 5 for most people (not for Chernoble survivors or Fernald workers)
  • Know that the Strong Nuclear Force is the glue that holds the nucleus together - it is very strong, but short range
  • Know what is meant by the term Binding Energy - don't worry about calculating binding energies
  • Be able to define nuclear fission and differentiate it from ordinary radioactive decay
  • Know that neutrons, fission fragments and a lot of kinetic energy are released when a nucleus undergoes fission
  • Understand that fission conserves nucleon number
  • Describe a 'chain reaction' - make sure you know the difference between subcritical,critical and supercritical
  • Have a general understanding of how a nuclear power plant generates electricity
Homework
  • Chapter 25  Questions:  3, 6, 7, 10, 11, 14, 15, 18, 23, 25, 28, 33, 46, 51, 55
  • Chapter 25  Exercises:  1, 9, 12
  • Chapter  26 Questions:  1, 2, 11, 37, 44, 45