Which expression gives the total number of nuclei that disintegrate during a time…

PHYSICS · Single correct · A Level · Physics · Nuclear physics · Nuclear physics

Problem

Which expression gives the total number of nuclei that disintegrate during a time interval

t

when the initial number of undecayed nuclei is

N_0

and the decay constant is

\lambda

? (a)

\displaystyle \Delta N = N_0 e^{-\lambda t}

(b)

\displaystyle \Delta N = N_0\bigl(1-e^{-\lambda t}\bigr)

(c)

\displaystyle \Delta N = N_0\lambda t

(d)

\displaystyle \Delta N = N_0(\lambda t) e^{-\lambda t}