If the fraction of the atoms of a radioactive material le...
If the fraction of the atoms of a radioactive material left after 120 years is 1/64, what is the half-life of the material?
24 years
20 years
10 years
2 years
Correct answer is B
Given amount remaining = 164
= 164=1(2)6
∴ = \frac{120 \text {years}}{6} = 20 years
\Rightarrow T\frac{1}{2} = 20 years