What is half-life?

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Question

What is half-life?

Accepted Answer

The time taken for half the radioactive nuclei in a sample to decay — After one half-life, half the unstable nuclei have decayed. After two half-lives, a quarter remain. After three, an eighth remain. And so on.

Answer

The time for activity to double

Answer

Half the life of a scientist

Answer

The time for all atoms to decay

Answer

The time taken for half the radioactive nuclei in a sample to decay

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