In a sample of radioactive material , what fraction of the initial number of active nuclei will remain undisintegrated after half of the half life of the sample ?

Options

A. `(1)/(2sqrt2)`
B. `(1)/(sqrt2)`
C. `2sqrt2`
D. `1/4`

Answer

B

Explanation

`N/N_0 = (1/2)^(t//T) " where " t = T/2`
`therefore N/N_0 = (1/2)^(T//2T) = (1/2)^(1//2) = 1/sqrt2`