Physics Topic 4

• What are the 3 types of radiation?

  Alpha, gamma and beta
• What are the 2 types of decay equations?

  Alpha decay: Larger nuclei. Nucleus ejects a helium nucleus (2 protons + 2 neutrons). Alpha radiation.

  241 237 4

  Am -> Np + He

  95 93 2

  Beta decay: Smaller nuclei. A neutron decays into a proton and electron. The high speed electron is beta radiation.

  14 14 0

  C -> N + e-

  6 7 -1
• What can all three types of nuclear radiation do?

  Ionise other atoms which is dangerous to living organisms.
• How can we detect radiation?

  With a Geiger-Muller (GM) tube
• What can alpha radiation be absorbed by?

  Paper
• What can beta radiation be absorbed by?

  A few mm of aluminium
• What can gamma radiation be reduced by?

  Gamma radiation's intensity can be reduced by lead & concrete
• What is radioactivity?

  The rate of decay in a sample of radioactive material. This is equal to the rate of the radiation emitted.

  The unit of radioactivity is Bq (becquerel)
• What is half-life?

  The time it takes for the activity/radioactivity to halve
• What is nuclear fission?

  Splitting of a larger/heavier nucleus into two daughter nuclei, releasing energy used to create electricity.
• What is nuclear fusion?

  Joining of two light nuclei to form a heavier nucleus, releasing energy.