Half-Life Calculator

Formula

Key Concepts

• Half-Life (t₁/₂): Time for half of the sample to decay
• Decay Constant (λ): Probability of decay per unit time
• Exponential Decay: N = N₀ × e^(-λt)
• Decay Rate: A = λN (activity at any time)

How to Use

1. Select the calculation type you want to perform
2. Choose appropriate time units
3. Enter the required values based on your calculation
4. Click Calculate to get the result

Common Applications

• Carbon-14 dating
• Medical imaging (PET scans)
• Nuclear power
• Archaeological dating
• Environmental monitoring

Important Notes

• All amounts must be positive
• Time must be non-negative
• Decay constant must be positive
• Remaining amount ≤ initial amount
• Units must be consistent

Example Values

• Carbon-14: t₁/₂ = 5,730 years
• Uranium-238: t₁/₂ = 4.5 billion years
• Iodine-131: t₁/₂ = 8.02 days
• Technetium-99m: t₁/₂ = 6.01 hours