Question

If a 10 gram sample of a radioactive substance has a half-life of 6000 years, how much would be present after 8000 years?

Answer 1

Given:

The amount of sample is

`N_o=\text{ 10 g}`

The half-life of the radioactive substance is

`T_{(1)/(2)}=\text{ 6000 years}`

Required: To find the amount of substance after t = 8000 years

Step-by-step explanation:

The amount of substance after 8000 years can be calculated by the formula

`N=N_o((1)/(2))^{_\frac{t}{T_{(1)/(2)}}}`

On substituting the values, the amount of substance will be

`\begin{gathered} N=10(0.5)^{(8000)/(6000)} \\ =\text{ 3.97 g} \end{gathered}`

Final Answer: The amount of substance present after 8000 years is 3.97 g