Half-Life Calculator | Calculate Decay Rates and Mean Lifetime
Calculate half-life, decay constants, and mean lifetime for radioactive materials. Free online calculator for nuclear decay and radiometric dating calculations.
Half-Life Calculator
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Common Radioactive Elements
View All →| Element | Half-Life | Common Use | Calculate |
|---|---|---|---|
| Carbon-14 | 5730 years | Carbon dating of organic materials | Calculate |
| Uranium-238 | 4.47 billion years | Radiometric dating of rocks | Calculate |
| Potassium-40 | 1.25 billion years | K-Ar dating method | Calculate |
| Iodine-131 | 8.02 days | Medical treatment and diagnostics | Calculate |
| Plutonium-239 | 24,100 years | Nuclear power and weapons | Calculate |
Key Formulas
Half-Life (t₁/₂)
t₁/₂ = ln(2) / λ
Where λ is the decay constant
Decay Constant (λ)
λ = ln(2) / t₁/₂
Inverse relationship with half-life
Mean Lifetime (τ)
τ = 1 / λ
Average time an atom exists before decay
Exponential Decay
N(t) = N₀(1/2)^(t/t₁/₂)
Where N₀ is initial quantity and t is time
Frequently Asked Questions
What is half-life?
Half-life is the time required for a quantity to reduce to half of its initial value. In radioactive decay, it's the time taken for half of a given sample to decay.
How is decay constant related to half-life?
The decay constant (λ) is inversely proportional to the half-life. It can be calculated using the formula λ = ln(2)/t₁/₂, where t₁/₂ is the half-life.
What is mean lifetime?
Mean lifetime (τ) is the average time an atom exists before undergoing decay. It's equal to the inverse of the decay constant (τ = 1/λ).
Why is half-life important?
Half-life is crucial in various fields including radioactive dating, nuclear medicine, and waste management. It helps determine the age of materials and calculate appropriate dosages in medical treatments.
Applications of Half-Life
Radiometric Dating
Used to determine the age of rocks, fossils, and archaeological artifacts by measuring the decay of radioactive isotopes.
Nuclear Medicine
Helps calculate proper dosages and timing for radioactive tracers and treatments in medical procedures.
Environmental Science
Monitors radioactive contamination and helps plan nuclear waste storage based on decay rates.
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About this Calculator
Calculate half-life, decay constants, and mean lifetime for radioactive materials. Free online calculator for nuclear decay and radiometric dating calculations.