Physics GCSE
Half-life
What Half-life means in Physics GCSE, as defined for OCR.
Definitions of Half-life
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Check what you remember
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Reference: OCR
The time taken for the number of undecayed nuclei in a sample to halve, or for the count rate from the sample to fall to half its starting value.
The time for the activity of a sample to halve.
Topics that use Half-life
- Radioactive emissions (OCR GCSE)
- Uses and hazards (OCR GCSE)
Related terms
- Absorbing materials
- Alpha emission
- Beta emission
- chain reaction
- conservation of charge
- conservation of mass number
- contamination
- Conventional nuclear notation
Using Half-life in the exam
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