# The decay constant of a radioactive sample is λ. The respective values of its half life and meanlife are

i) 1λ and (loge2)

ii) loge2λ and 1λ

#### We have decay equation as follows

Remaining nuclei , N=N0e−λt ..................(1)

We know that for t=half−life we get remaining nuclei as half of initial nuclei(N0)

i.e N=N0/2 so using this with t=t1/2 in equation-1 we get

t1/2=loge2λ

Mean life is nothing but time(T) for which N=N0/e

so using it in equation-1 we get T=1λ

Option 2 is correct.