एक रेडियोएक्टिव पदार्थ की एक्टिविटि `R_(1)` समय `t_(1)` पर है तथा `R_(2)` समय `t_(2)` पर है। यदि विघटन नियतांक `lambda` हो तो

Options

A. `R_(1)= R_(2) e^(lambda(t_(1)-t_(2))`
B. `R_(1)=R_(2)^(t_(2)//t_(1))`
C. `R_(1)=R_(2)`
D. `R_(1)= R_(2)e^(-lambda(t_(1)-t_(2))`

Answer

D

Explanation

`R_(1)= (dN_(1))/(dt)= -lambdaN_(1), R_(2)= (dN_(2))/(dt)= -lambdaN_(2)`
`(R_(1))/(R_(2))= (lambdaN_(1))/(lambdaN_(2))= (N_(1))/(N_(1)e^((-lambda)(t_(2)-t_(1))))= e^(lambda(t_(2)-t_(1)))`
`R_(1)=R_(2)e^(lambda(t_(2)-t_(1))= R_(2)e^(-lambda(t_(2)-t_(1))`