Answer:
The statistical uncertainty of this measurement is 0.3 s.
(A) is correct option.
Step-by-step explanation:
Given that,
Time for a ball to fall is measured three time as,
![t_(1)=4.8\ s](https://img.qammunity.org/2021/formulas/physics/college/8qdlsw9b4vwfvt77fkukw2g3w7em22ees1.png)
![t_(2)=8.2\ s](https://img.qammunity.org/2021/formulas/physics/college/ar6hdolwhrwlsa2j0oa1hatp3kystqn0kq.png)
![t_(3)=7.4\ s](https://img.qammunity.org/2021/formulas/physics/college/qz357xq374se834x5h71nvq8eapiywunmj.png)
The same uncertainty of ± 0.4 s.
We need to calculate the statistical uncertainty of this measurement
Using formula of statistical uncertainty
![uncertainty=\sqrt{((\mu)/(t_(1)))^2+((\mu)/(t_(2)))^2+((\mu)/(t_(2)))^2}](https://img.qammunity.org/2021/formulas/physics/college/i83wsnsp7h5wr9fbczgq4d8cglglsp80kc.png)
Put the value into the formula
![uncertainty=\sqrt{((0.4)/(4.8))^2+((0.4)/(8.2))^2+((0.4)/(7.4))^2}](https://img.qammunity.org/2021/formulas/physics/college/lh9fq60sl4pkkdirfz7k17r8j940d9yqbz.png)
![uncertainty=0.1\ s](https://img.qammunity.org/2021/formulas/physics/college/6xupkz4uc2bezpt6otfjkw0uhlbf2gtgb9.png)
The nearest answer will be 0.3 s.
Hence, The statistical uncertainty of this measurement is 0.3 s.
(A) is correct option.