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Half-Life Formula

t½ = ln2 / λ

What it means

The half-life is the time for half of a radioactive sample to decay, related to the decay constant.

Variables

SymbolQuantitySI unit
half-lifes
λdecay constant1/s

Worked example

Given λ = 0.05 1/s, solve for :

t½ = 13.8629 s

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