Sample of two radioactive nuclides `A` and `B` are taken. `lambda_(A)` and `lambda_(B)` are the disintergration constants of `A` and `B` respectively. In which of the following cases, the two sample can simultaneously have the same decay rate at any time ?

Options

A. Initial rate of decay of A is twice the initial rate of decay of B and `lambda_(A)=lambda_(B)`
B. Initial rate of decay of A is twice the initial rate of decay of B and `lambda_(A)gtlambda_(B)`
C. Initial rate of decay of B is twice the initial rate of decay of A and `lambda_(A)gtlambda_(B)`
D. Initial rate of decay of B is same as the rate of decay of A at t=2h and `lambda_(B)=lambda_(A)`

Answer

B, D

Explanation

The two samples of two radioactive nuclides A and B can simultaneously have the same decay rate at any time if initial rate of of decay A is twice the initial rate of decay of B and `lambda_(A)gtlambda_(B)`. Also, when initial rate of decay of B is same as rate of decay of A at t=2h and `lambda_(B) ltlambda_(B)`. The choice (b) and (d) is correct.