Question

if co-60 gamma sources have a half life of 5.27 years. if you had a 10 g sample of Co-60 how much would still be present after 21 years

Answer 1

Answer:

2.684 g

Explanation:

Given:

half life (T) = 5.27 years

Initial amount (N₀) = 10 g

time (t) = 21 years

$\boxed{Final\ amount\ (N)=(\frac{1}{2})^{\frac{t}{T}}\cdot N_o}$

$N=\frac{1}{2} ^{\frac{10}{5.27}} \times10$

   $=2.684\ g$