10 minutes maximum! Can you do it in 5?


A patient in a hospital is injected with a radioactive isotope. Special cameras outside the body can follow the path of the isotope to diagnose medical conditions.

This is known as a medical tracer.

PET animation

 1. Which type of radiation will pass most easily through body tissues?

  • A. alpha
  • B. beta
  • C. gamma
  • D. all three pass easily through the body

2. If you are injecting a patient with this type of tracer, what length half-life is most realistic so that you can take pictures and not harm the patient?

  • A. a few years
  • B. a few hours
  • C. a few seconds
  • D. a few months

Q3-8. These questions are about Nuclear Power:

radiation hazard

3. Which element is the fuel source for a nuclear power station?

  • A. Hydrogen
  • B. Lead
  • C. Uranium
  • D. Potassium

4. What is the name given to the process of splitting atoms to release energy?

  • A. Nuclear fission
  • B. Nuclear fusion
  • C. Atomic breakdown
  • D. Thermal splitting

5. What is the name of the particle that hits the nuclear fuel atoms and starts the process going?

  • A. alpha
  • B. electrons
  • C. neutrons
  • D. protons

6. When the atom splits, it releases 2 or 3 more of these particles which go on and split more fuel atoms, and so on. This process is called a....

  • A. chain reaction
  • B. cascade reaction
  • C. avalanche reaction
  • D. nuclear multiplier reaction.

7. What form / store of energy do all the products of this reaction have?

  • A. thermal energy
  • B. kinetic energy
  • C. chemical energy
  • D. elastic energy

8. This is a diagram of a nuclear reactor. When the green rods are lifted, the reaction rate increases.

What is the name given to the green rods and what do they do?

Name Function
moderator absorb neutrons
moderator slow down neutrons
control rod absorb neutrons
control rod slow down neutrons

Q9 & 10.

These questions are about an aluminium foil factory. The foil is made thin by 2 rollers that squeeze the aluminium into a thin sheet.

A radioactive source and a detector are used either side of the sheet to measure how thick the foil is, and make automatic adjustments to the rollers if needed.


use of radioactivity in foil mill

9. Which type of radiation should be emitted by the source?

  • A. alpha
  • B. beta
  • C. gamma
  • D. all three would work

10. The half-life of the source needs to be suitable to stop the detector making unnecessary changes to the rollers. How long should the half-life be, and what would happen to the foil thickness if it was the wrong length half-life?

The half-life should be..... ...otherwise the foil will eventually be made too...
short thick
short thin
long thick
long thin