Radiation

• What is the symbol for alpha radiation?


  (Open horizontal infinity sign)
• What is the symbol for beta radiation?

  β
• What is the symbol for gamma radiation?


  (Open vertical infinity sign)
• What is the relative mass and relative charge of a proton?

  1, +1
• What is the relative mass and relative charge of a neutron?

  1, 0
• What is the relative mass and relative charge of an electron?

  1/2000, -1
• What is a nucleon?

  an A number, proton or neutron
• What is a proton?

  Z number, number of protons
• What is random decay?

  • Atoms like to be stable
  • When atoms have an imbalance between the number of protons and neutrons, they will spit out energy or particles
  • Once stable, they are less likely to decay
  • Radioactive decay is completely random
• What is nuclear radiation?

  • Comes from the centre (nucleon) of the atom
  • Three types (alpha, beta, gamma)
  • Atom changes when radiation is released
• What does a Geiger counter do?

  Counts the amount of radiation given off in a given timeframe
• A background radiation reading is taken before putting a source in front of the GM tube. We deduct this reading from the total
• What is ionisation?

  • Radiation can change DNA and ionise cells
  • High damage kills the cells
  • Lower damage causes cancer
  • Alpha radiation is the most ionising in the body
  • Gamma radiation is the most ionising out of the body
• Alpha radiation


  If an alpha particle is produced, then the number of protons goes down by 2, mass number goes down by 4. The atom becomes a different element, two places below in the periodic table e.g. oxygen becomes carbon after alpha decay
• Beta radiation

  If a beta particle is produce, then the number of protons goes up by 1. The atom becomes a different element, one place up in the periodic table e.g. carbon becomes nitrogen after beta decay
• Gamma radiation

  Gamma radiation makes no change, it only released energy that makes the atom more stable
• What pole of a magnet is beta radiation attracted to?

  North (+)
• What pole of a magnet is alpha radiation attracted to?

  South (-)
• What pole of a magnet is gamma radiation attracted to?

  Neither
• What is background radiation?

  Comes from underground rocks and comes up through floors. Radon decays to form alpha particles, which are the most ionising in the body and can cause lung cancer
• How can you prevent radon gas?

  Fan in floor/attic or airbricks
• Disposing of radiation

  • There are 3 levels of waste
  • Low level waste can be bagged and put into landfill
  • Medium level waste can be put into landfill if it’s short-lived, otherwise it is disposed with high level waste
  • High level waste has to be buried underground
• What is half life?

  The time taken for the count rate (using a Geiger counter) of a radioactive source to decrease by half
• What is a ‘safe’ sample?

  Producing radiation that would be indistinguishable from background radiation
• What does too-short of a half life mean for an item?

  Dispose of the item more frequently
• What does too-long of a half life exposure mean for a human?

  Causes damage to human cells
• What is one use of gamma radiation in sterilisation?

  Sterilisation of food & medical equipment
• What type of radiation is used for sterilization?

  Gamma
• Why is gamma radiation used for sterilization?

  It has a long half-life, lasting several years
• What is the half-life of gamma radiation used in radiotherapy?

  A few hours
• Why is the half-life of gamma radiation important in cancer treatment?

  It allows for short-term effects in treatment
• What is the use of gamma radiation in medical tracers?

  To track medical conditions
• What type of radiation is used in smoke alarms?

  Alpha
• Why is alpha radiation used in smoke alarms?

  It has a long half-life, lasting years
• What type of radiation is used for monitoring paper thickness?

  Beta
• Why is beta radiation used for monitoring paper thickness?

  It has a long half-life, lasting years
• What types of radiation are used for checking cracks in underground pipes?

  Beta/gamma (depending on depth)
• Why is it important to monitor cracks in underground pipes?

  To prevent contamination
• What is the significance of the half-life in radiation applications?

  It determines how often the source needs replacement
• How does sterilising food/medical equipment work?

  Gamma rays kill bacteria, mould and insects - even when food is packaged, but it can effect the taste. Used to kill bacteria on hospital equipment also and is useful with plastic equipment that would be damaged by heat sterilisation