Radioactive decay
Unstable nuclei give out radiation to become more stable
Activity of an unstable nucleus
Rate of decay of unstable nuclei
Count rate
Number of radioactive decays per second
Half life
Time it takes for unstable nuclei to halve
Radioactive contamination
Unwanted radioactive nuclei get on other materials
Irradiation
Exposed to nuclear radiation
Radius of an atom
1*10 to the power of -10
4 sources of background radiation
Cosmic rays from space
Rocks
Nuclear weapons testing
Nuclear explosions
Nuclear fission
The splitting of a large unstable nuclei into a smaller stable nuclei
3 main components
Control rods
Fuel rods
Moderator
Fissile
When the fission of nuclei is induced through the absorption of slow neutrons
Nuclear fusion
When 2 light nuclei join together to form a heavier nuclei
Fissionable isotope
Uranium-235
Moderator
Slows down neutrons
Right speed for absorption
2 isotopes of hydrogen which are commonly used in nuclear fusion
Deuterium and tritium
