Half-life is the time required for half of the radioactive nuclei in a sample to undergo radioactive decay. It's a fundamental concept in nuclear physics, chemistry, and medicine. The half-life is constant for each radioactive isotope and is independent of the initial amount of the substance.
The half-life formula is based on exponential decay: N(t) = N₀ × (1/2)^(t/t₁/₂)
Where:
Enter the Initial Quantity (N₀) - the starting amount of the radioactive substance.
Enter the Half-Life (t₁/₂) - the time it takes for half of the substance to decay.
Enter the Time Elapsed (t) - how much time has passed since the beginning.
Select the appropriate Time Unit (seconds, minutes, hours, days, or years).
Click "Calculate Remaining Quantity" to see the results and step-by-step calculation.
Half-life: ~5,730 years
Used in radiocarbon dating
Half-life: ~4.5 billion years
Used in nuclear fuel
Half-life: ~8 days
Used in medical treatments
Half-life: ~6 hours
Used in medical imaging
Carbon dating to determine age of artifacts and fossils
Medical imaging, cancer treatment, and pharmaceutical research
Nuclear power generation and waste management planning