radiation

Cards (20)

  • alpha is a helium nucleus , atomic mass of 4, charge is 2 , short penetration , absorbed by cells , highest ionisation density
  • beta is a fast moving electron , charge is -1 , penetrates a few meters, can pass cells
  • gamma is a high frequency EM wave, unlimited penetration , unlikely to pass through cells
  • ioisation is an atom gaining or losing an electron to become an ion
  • ionisation density is when a particle loses energy by the medium absorbing it
  • beta used to detect blood clots and gamma is used for tracers
  • fission is when a large nucleus is broken into 2 smaller nuclei releasing energy and neutrons
  • fission is spontaneous
  • fusion is 2 small nuclei fusing to create a larger nucleus
  • fission chain reaction- neutrons produce additional fission to atleast one other nucleus
  • fission is used in nucllear power stations to produce energy
  • fusion requires high temperatures so plasma containment is used instead
  • absorbed dose is the radiation energy absorbed per kilogram of mass
  • equivelant dose is the biological harm caused by radiaion
  • the limit for the public is 2.2msv and the limit for a worker is 20mSv
  • activity is the number of nuclear decays per second
  • background radiation from gas in the ground/ rocks/ cosmic microwaves
  • to measure activity measure the background radiation for 1 inute then record record source radiation at each subsequent minute and subtract background radiation
  • half life is the time taken for activity to fall by half
  • to measure half life measure the count at set time intervals the count at regular intervals and subtract background radiation