Question

The half-lfe of ${}^{198}Au$ is 2.7 days. The average life is

• A. 4 days
• B. 3.4 days
• C. 3.9 days
• D. None of the above

Answer 1

The correct option is C 3.9 days

The average life $\tau$ and half-life $T_{1/2}$ of a radioactive substance are related as:

$\tau =1.44\times T_{1/2}$

Given: $T_{1/2}=2.7days$

Hence, average life, $\tau =1.44\times 2.7=3.9days$