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At time t=0 N(1) nuclei of decay constan...

At time `t=0 N_(1)` nuclei of decay constant `lambda_(1)& N_(2)` nuclei of decay constant `lambda_(2)` are mixed. The decay rate of the mixture at time 't' is:

A

`N_(1)N_(2)e^((lambda_(1)+lambda_(2))t)`

B

`+((N_(1))/(N_(2)))e^(-(lambda_(1)-lambda_(2))t)`

C

`+(N_(2)lambda_(1)e^(lambda_(1)t) + N_(2)lambda_(2)e^(-lambda_(2)t))`

D

`+N_(1)lambda_(1)N_(2)lambda_(2)e^(-(lambda_(1)+lambda_(2))t)`

Text Solution

Verified by Experts

The correct Answer is:
C
`(dN)/(dt)= lambda_(1)N_(1)+lambda_(2)N_(2) implies lambda_(1)N_(10)e^(-lambda_(1)t)+lambda_(2)N_(20)e^(-lambda_(2)t)`
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