The equations `(dN)/(dt) = - lambda N` and `N = N_(0)e^(- lambda t)` describes how the number N of undecayed atoms in a sample of radioactive material, which initially (at `t = 0`) contained `N_(0)` undecayed atoms, varies with time t. Which one of the following statements about `lambda` is correct ?

Options

A. `lambda delta t` gives the fraction of atoms present which will decay in the next small time interval `delta t`
B. `lambda` is the time needed for N to fall from N0 to the value `N_(0)//e`
C. `lambda` is the number of atoms left after a time equal to e second.
D. `lambda` is the chance that any one atom will still be undecayed after one second.

Answer

A