Radioactivity
Radioactivity is the spontaneous emission of radiation from unstable atomic nuclei, involving alpha, beta, and gamma radiation types.
Core concept
Alpha particles are helium nuclei (2 protons, 2 neutrons), having low penetration power but high ionising ability.
How it works
Beta particles are high-speed electrons, having moderate penetration power, more than alpha but less than gamma radiation.
Why it matters
Gamma rays are high-energy electromagnetic radiation, having the highest penetration power but lower ionising ability compared to alpha and beta.
Key detail
Radioactivity has applications in medicine (cancer treatment, diagnostics), power generation (nuclear reactors), and carbon dating for determining age of ancient materials.
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• Alpha particles: helium nuclei (2p, 2n).
• Alpha has low penetration, high ionising ability.
• Beta particles: high-speed electrons.
• Beta has moderate penetration power.
• Gamma rays: high-energy electromagnetic radiation.
• Gamma has highest penetration, lower ionising ability.
• Applications: medicine, power generation, carbon dating.
• Radioactivity comes from unstable nuclei.