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What half-life means

What half-life means

Half-life is the time taken for half the undecayed nuclei in a radioactive sample to decay. Equivalently, it is the time taken for the activity or count rate of a source to fall to half its starting value.

6.4 Half-life Lesson

  1. GCSE
  2. /Physics
  3. /6.4 Half-life

Step-by-step lessons on Edexcel GCSE Physics 6.4 Half-life, covering 6.4.1 Activity and its decrease over time, 6.4.2 Half-life and its random nature, and 6.4.3 Half-life calculations. Each one builds up to exam-style questions. Master the required practical work and core equations early, since both papers can draw on content and maths skills from across the whole specification.

Lessons