Suppose the daughter nucleus in a nuclear decay is itself radioactive. If λd and λm, denote the decay constants of daughter and mother nuclei and Nd and Nm, the numbers of daughter and mother nuclei present at a time, then the number of daughter nuclei becomes constant when 

(a) λm Nm = λNd

(b) λm Nd = λNm

(c) Nm - Nd = λ-  λd

(d) Nm + Nd = λm +  λd

4 views

1 Answers

The correct option is (a) λm Nm = λNd

Explanation:

The number of mother nuclei decaying in a short time interval dt is Nm λdt But death of a mother nucleus implies the birth of a daughter nucleus. 

The number of daughter nuclei decaying in the same time interval is Nd λdt. 

The number of daughter nuclei will remain constant when

Nm λdt  = Nd λdt

λm Nm = λNd

4 views