Bunding enertgy
On the graph of binding energy vs mass number, what is the point seperating fission and fusion
(56,8.7MeV)
what is the y axis and x axis on graph comparing fission and fusion
x - Massnumber
Y- Binding energy per nucleon (MeV)
What is too the left and right of the graph? Fusion or fission
Fusion left and fission right
What is nuclear fission
Heavy nuclei
splits into two smaller nuclei neutrons and beta particles
two smaller nuclei more stable
energy difference released
What is nuclear fusion
Get so close stron force takes over and lots of energy is released
Why is fusion better than fission
Suplly fuel unlimited (sea water)
Fewer waste products
Energy release per unit mass is greater
Fuel rods
uranium 235
Chain reaction of thermal neutrons
U235 more fissile than 238
Fuel rods contain both isotopes
what is a thermal neutron
Neutron in thermal equillibrium
Comtrol rods
Material that absorbs neutrons (boron,silver)
safety feature
can be activated at any time
Moderator
reduces energy of neutrons
Graphite or water
Lose energy due to collision with water molecules
What are the safety features of a nuclear power station
Thick steel pressure vessel which absorbs beta radiation
Thick concrete walls which absorbs gamma and neutrons
Emergency shut down system
Used fuel rods are removed and replaced