Answers to Physics Questions

1.	Answer the following questions by typing your answers into a text file and posting it back here as a .doc (word document file). For Help, use the Help & Resources menu link.
1. What is the number of neutrons in the U-235 nucleus?
2. When a neutron in absorbed by a U-235 nucleus, what is the resulting element, nucleon number and neutron number?
3. Carbon-14 decays emitting an electron (beta decay). What is the resulting element, nucleon number and neutron number?
4. Iodine-131 is radioactive with a half-life of 8.05 days. How long does it take for a sample to decay to one-eighth of its original number of nuclei?
5. U-236 is unstable and undergoes fission into Ba-141 and Kr-92. Determine the number of neutrons which are emitted in the process.
6. What is the function of the moderator in a nuclear reactor?
7. In a few sentences, explain the operation of a breeder reactor.
8. Do a search for information about the Pebble Bed reactor.  What are the features that distinguish it from the typical water-cooled reactor?