Consider the situation of the previous problem. Suppose the production of the radioactive isotope starts at t = 0. Find the number of active nuclei at time t.
Let N˳ is the radioactive isotope present at time t=0
N be the radioactive isotope present at time t
And λ be the disintegration constant.
By Law of Radioactivity,
No. of particles decay = N˳-N= N˳ (1- ⅇ-λt)
As the production starts at t=0.
So,
Activity
⇒