Thread: half life

Find the half-life (in hours) of a radioactive substance that is reduced by 15 percent in 60 hours

Originally Posted by cwarzecha

Find the half-life (in hours) of a radioactive substance that is reduced by 15 percent in 60 hours

Again
$\displaystyle A(t) = A_0 \left ( \frac{1}{2} \right ) ^{t/t_{1/2}}$

So
$\displaystyle \frac{A(t)}{A_0} = 0.15 = \left ( \frac{1}{2} \right ) ^{60/t_{1/2}}$
Solve for $\displaystyle t_{1/2}$.

-Dan