Radiation

• What is alpha radiation


  helium nucleus

  2p 2n
• What is beta radiation


  High energy electron from nucleus
• What is gamma radiation

  High energy electro magnetic wave which travels at the speed of light
• relative mass of alpha particle


  4
• Relative mass of beta

  ~1/2000
• Relative mass of gamma wave

  0
• Relative charge of alpha particle 


  +2
• Relative charge of beta 


  -1
• Which is the most ionising, alpha beta gamma?

  alpha
• Which has The highest penetrating power? Alpha beta gamma?


  Gamma
• What is gamma radiations range in air?

  infinite
• Natural sources of radiation

  Granite

  Radon gas in air

  Cosmic rays
• Artificial sources of radiation

  Fallout from nuclear weapon testing

  Radiography department

  Nuclear waste

  Nuclear accidents
• Units of radiation dose

  Sieverts
• Which radiation is the most dangerous inside your body?

  alpha source
• Which is the most dangerous radiation Outside your body?

  Beta source
• Nuclear fission


  Large nuclei splitting
• Nuclear fusion

  Small nuclei fusing
• Fission process

  Low energy neutron combines with u235

  to give u236

  Fission occurs releasing daughter nuclei +3neutrons + energy
• Fusion process

  Small nuclei fuse into larger nucleus releasing energy

  Electrostatic repulsion between nuclei makes this difficult
• NFR


  nuclear fusion reactor
• NFR fuel rods


  Assembled into rods, they can be insterted and removed to load and unload the reactor, each of these it used for a few months until the amount of u235 is greatly reduces
• NFR control rods


  these are made if materials that absorb neutron such as boron if they are fully inserted the chain reaction stops , if they are moved out the reaction starts going faster and faster
• NFR moderator


  The gaps between the fuel rods and control rods are filled with this it is usually carbon or heavy water the job of this part is tk slow down the neutrons emitted by u235 without it the neutrons will be going too fast and will escape without causing fission
• NFR cooling unit


  This is used to remove heat , pressurised water js circulated through the reaction core, then it goes through the sealed pipes to and from a heat exchanger, the water is used to turn turbines once it has extracted the heat.
• NFR vessel


  This is where the fission takes place