radioactive decay (idea) by wangmu

If you have N₀ atoms of a radioactive isotope at time 0, the number N which you have at time t is given by the equation:

N = N₀ e^{-λ t}

Here lambda is the "decay constant", a measure of how fast the isotope decays. It is equal to (ln 2) divided by the half-life.

The equation above can be derived from the fact that since each atom of a radioactive isotope has an equal probability of decaying in a given time period, the rate of decay is proportional to the number of radioactive atoms present, i.e.:

dN/dt = -λ N.

alpha decay	beta decay	Uranium mining on reservations in the southwestern United States	Half-life
phosphorus-32	Irradiator	isotope	radiation exposure
Ernest Rutherford	radioactive	positron emission	Radioisotope thermoelectric generator
Nuclear decay	Radiometric dating	exponential	probability
electron capture	Crush, Crumble, and Chomp!	Pebble Bed Modular Reactor	CNO cycle
Yucca Mountain	Nuclear Regulatory Commission	Nuclear decommissioning costs	Twinkies: A scientific study