Common Radioactivity Levels
1 Ci = 3.7×10¹⁰ Bq
Basic conversion
15 pCi = 0.555 Bq
Background radiation level
100 mCi = 3.7 GBq
Medical isotope dose
4 pCi/L = 148 Bq/m³
EPA radon action level
Absorbed Dose Examples
1 Gy = 100 rad
Basic conversion
0.01 mGy = 10 μGy
Chest X-ray dose
7 mGy = 0.7 rad
CT scan dose
2 Gy = 200 rad
Radiation therapy fraction
🔬 Nuclear Physics & Radioactive Decay
Fundamental Decay Law
Radioactive decay follows an exponential law where the number of unstable nuclei decreases over time according to their decay constant λ (lambda).
N(t) = N₀ × e^(-λt)
t₁/₂ = ln(2)/λ = 0.693/λ
Where N₀ is initial activity, λ is decay constant, and t₁/₂ is half-life.
Interactive Decay Visualization
Click buttons to see different decay scenarios
Explore how different isotopes decay at different rates
📚 History of Nuclear Discovery
1896
Henri Becquerel discovers radioactivity in uranium salts
1898
Marie & Pierre Curie discover radium and polonium
1902
Ernest Rutherford identifies alpha and beta radiation
1911
Rutherford discovers atomic nucleus structure
1932
James Chadwick discovers the neutron
1938
Otto Hahn discovers nuclear fission
🧪 Common Radioisotope Database
Carbon-14
Half-life: 5,730 years
Decay: β⁻ → Nitrogen-14
Use: Radiocarbon dating
Decay: β⁻ → Nitrogen-14
Use: Radiocarbon dating
Iodine-131
Half-life: 8.02 days
Decay: β⁻ → Xenon-131
Use: Thyroid treatment
Decay: β⁻ → Xenon-131
Use: Thyroid treatment
Cobalt-60
Half-life: 5.27 years
Decay: β⁻ → Nickel-60
Use: Cancer therapy
Decay: β⁻ → Nickel-60
Use: Cancer therapy
Uranium-238
Half-life: 4.47 billion years
Decay: α → Thorium-234
Use: Nuclear fuel
Decay: α → Thorium-234
Use: Nuclear fuel
Technetium-99m
Half-life: 6.01 hours
Decay: γ → Technetium-99
Use: Medical imaging
Decay: γ → Technetium-99
Use: Medical imaging
Radon-222
Half-life: 3.82 days
Decay: α → Polonium-218
Use: Natural background
Decay: α → Polonium-218
Use: Natural background
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