mean life

noun Physics.

the average time that an unstable particle or nucleus survives before it decays.
decay time.

Also called average life, lifetime.

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British Dictionary definitions for average life

mean life

noun

physics the average time of existence of an unstable or reactive entity, such as a nucleus, elementary particle, charge carrier, etc; lifetime. It is equal to the half-life divided by 0.693 15Symbol: τ

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