← 2.2 Radioactivity and Stability of Isotopes
Half-life is a constant
Physics · Grade 10 · about 40 minutes
The time for half the nuclei to decay never changes, and the sample never quite reaches zero.
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- 8 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
- Your progress kept across every subject you take
Other lessons in this sub-strand
- The unstable nucleus and its radiations
- Nuclear equations and half-life
- Fission, fusion, applications and safety
- The nucleus and its nucleons
- Isotopes of the same element
- The neutron-to-proton ratio
- The strong force and why large nuclei fail
- Alpha radiation close up
- Beta particles from the nucleus
- Gamma rays: energy only
- Ionisation against penetration
- Alpha, beta and gamma in fields
- The Geiger–Müller tube
- Film, cloud chamber and electroscope
- Background radiation in Kenya
- Writing nuclear equations
- Decay series until stability
- Half-life is a constant
- Half-life calculations
- Decay curves and background
- Modelling half-life with dice and a burette
- Carbon-14 dating of wood and bone
- Fission, fusion and control
- Hospitals, mines and safety in Kenya