Combined Science GCSE
half-life
What half-life means in Combined Science GCSE, as defined for AQA.
Definitions of half-life
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Reference: AQA
The time it takes for the number of nuclei of the isotope in a sample to halve, or for the count rate from a sample to fall to half its initial level.
The time after which the count rate or activity of a radioactive sample falls to half its previous value.
Topics that use half-life
Related terms
- Experimental variation and reliability of measurements
- Halving of nuclei number and count rate
- net decline
- Random nature of radioactive decay
- Statistical predictability of large samples
- Half-life and activity
- Half-life as a measurable constant
- Practical applications of half-life
Using half-life in the exam
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