Two radioactive nuclei A and B have their disintegration constant lambda_(A) and lambda_(B) respectively. Initially N_A and N_B number of nuclei are taken, then the time after which their undisintegrated nuclei are same is :

Two radioactive nuclei A and B have their disintegration constant lamb

1.	Two radioactive nuclei A and B have their disintegration constant lambda_(A) and lambda_(B) respectively. Initially N_A and N_B number of nuclei are taken, then the time after which their undisintegrated nuclei are same is :
Answer» `(lambda_(A) lambda_(B))/((lambda_(A)-lambda_(B))) ln (N_(B))/(N_(A))` `(1)/((lambda_(A)+lambda_(B))) ln (N_(B))/(N_(A))` `(1)/((lambda_(B)-lambda_(A))) ln (N_(B))/(N_(A))` `(1)/((lambda_(A)-lambda)) (N_(B))/(N_(A))` Solution :`N_(A) .e^(-lambda A^(t))=N_(B).e^(-lambda B^(t))` `e^((lambda_(B)-lambda_(A))t)=(N_(B))/(N_(A))` `(lambda_(B)-lambda_(A))=ln ((N_(B))/N_(A))` `t=(1)/(lambda_(B)-lambda_(A)) ln ""N_(B)/(N_(A))`

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Two radioactive nuclei A and B have their disintegration constant lambda_(A) and lambda_(B) respectively. Initially N_A and N_B number of nuclei are taken, then the time after which their undisintegrated nuclei are same is :

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