What is mean life of radioactive element?
Mean life, in radioactivity, average lifetime of all the nuclei of a particular unstable atomic species.
This time interval may be thought of as the sum of the lifetimes of all the individual unstable nuclei in a sample, divided by the total number of unstable nuclei present..
What is average life period?
The average life is the length of time the principal of a debt issue is expected to be outstanding. … In loans, mortgages, and bonds, the average life is the average period of time before the debt is repaid through amortization or sinking fund payments.
What is the relation between half life and average life?
Note that the radioactive half-life is not the same as the average lifetime, the half-life being 0.693 times the average lifetime. The example that causes the most confusion is the decay of the free neutron with a half-life of 10.3 minutes and an average lifetime of 14.9 minutes.
What radioactive element has the longest half life?
BismuthBismuth breaks half-life record for alpha decay. Physicists in France have measured the longest ever radioactive half-life – over twenty billion billion years – in a naturally occurring element that decays by emitting alpha-particles.
What is the mean of radioactive?
: the property possessed by some elements (such as uranium) or isotopes (such as carbon 14) of spontaneously emitting energetic particles (such as electrons or alpha particles) by the disintegration of their atomic nuclei also : the rays emitted.
What is the life of an atom?
Ultimately, even these stable atoms have a limit imposed by the lifetime of proton (>1025 years). Remember, though, that the best estimate of the present age of the universe is the much smaller number of 1010 years, so for all practical purposes, atoms are forever.