Question

For a radioactive element, $\tau =$ ______${\tau }_{1/2}$

• A. $0.693$
• B. $693$
• C. $144$
• D. $1.44$

Answer 1

Answer: (D)

${\tau }_{\text{mean }}\times \ln 2={\tau }_{1/2}$
${\tau }_{\text{mean }}={\tau }_{1/2}(1/\ln 2)$
$=1.44{\tau }_{1/2}$