A radioactive isotope is being produced at a constant rate dN/dt = R in an experiment. The isotope has a half-life t1/2. Show that after a time t >> t1/2, the number of active nuclei will become constant. Find the value of this constant.
Given, rate of radioactive isotope production= R
Rate of decay= λN (∵ According to law of Radioacivity)
As activity decreases exponentially and after a time t >> t1/2, the number of active nuclei will become constant and rate of decay will also become constant.
So, (dN/dt) produce=(dN/dt) decay=R
R= λN
⇒ N= =