1.

Two radioactive materials X_1 and X_2 have decay constants 10lambda and lambdarespectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of X_1 to that of X_2 will be 1/e after atime

Answer»

`1/(10lambda)`
`1/(11lambda)`
`11/(10lambda)`
`1/(9lambda)`

SOLUTION :Given : `N_1/N_2=1/e because N=N_0e^(-lambdat)`
`therefore (N_0e^(-10lambdat))/(N_0e^(-lambdat))=1/e` or `1/e^(9 lambdat)=1/e` or `9lambdat=1` or `t=1/(9lambda)`


Discussion

No Comment Found

Related InterviewSolutions