PhysicsCode 5054
Half-life
What this topic asks you to be able to do
- Define the half-life of a given isotope as the time needed for half of the nuclei in a sample of it, of any size, to decay; recall this definition and use it in calculations which may involve data from tables or decay curves
- Outline how carbon-14 (14C) is used to date objects
- Explain how the kind of radiation given out and the half-life of an isotope decide which isotope is chosen for uses including: (a) smoke alarms for fires in the home (b) irradiating food so that bacteria are killed (c) sterilising equipment with gamma rays (d) measuring and controlling how thick materials are, with the radiation chosen according to how it penetrates and is absorbed (e) diagnosing and treating cancer with gamma rays