Question

Obtain the relation N = N₀e^-λt  for a sample of radio active material having decay constant   λ , where N is the number of nuclei present at instant t. Hence obtain the relation between decay constant  λ and half life T_1/2 of the sample. 

Answer 1

Let a sample of radioactive material have N₀ nuclei,at t = 0

At time t, Number of nuclei = N

As per the decay law