A radioactive substance emits 100 beta particles in the first 2 seconds and 50 beta particles in the next 2 seconds. The mean life of the sample is

Options

A. 4 seconds
B. 2 seconds
C. `(2)/(0.693)` seconds
D. `2 xx 0.693` seconds

Answer

C

Explanation

The half life of the radioactive substance is
`T_(1//2) = 2` seconds
Mean life = `(T_(1//2))/(In 2) = (2)/(0.693)` seconds