Key Concepts: Half-Life Calculations

Core Definitions

• Half-Life (t½): The time it takes for half of a radioactive sample to decay.
• Formula: Remaining = Original × (½)ⁿ, where n = number of half-lives elapsed.
• Finding n: n = total time ÷ half-life.
• Key Feature: Half-life is constant — it does not change regardless of the amount of sample.