← 2.2 Radioactivity and Stability of Isotopes

Background radiation in Kenya

Physics · Grade 10 · about 40 minutes

Rocks, radon, cosmic rays, food and a little medicine — always there, always subtracted.

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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
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