Respuesta :

Answer:

  • 4.77 %

Explanation:

We know that the volume V for a sphere of radius r is

[tex]V(r) = \frac{4}{3} \ \pi \ r^3[/tex]

If we got an uncertainty [tex]\Delta r[/tex] the formula for the uncertainty of V is:

[tex]\Delta V(r) = \sqrt{  (\frac{dV}{dr} \Delta r)^2  }[/tex]

We can calculate this uncertainty, first we obtain the derivative:

[tex]\frac{dV}{dr}  = 3 * \frac{4}{3} \ \pi \ r^2[/tex]

[tex]\frac{dV}{dr}  = 4 \ \pi \ r^2[/tex]

And using it in the formula:

[tex]\Delta V(r) = \sqrt{  (4 \ \pi \ r^2\Delta r)^2  }[/tex]

[tex]\Delta V(r) = \sqrt{  4^2 \ \pi^2 \ r^4 \Delta r^2  }[/tex]

[tex]\Delta V(r) =  4 \  \pi \ r^2 \Delta r [/tex]

The relative uncertainty is:

[tex]\frac{\Delta V(r)}{V(r)}[/tex]

[tex]\frac{ 4 \  \pi \ r^2 \Delta r  }{ \frac{4}{3} \ \pi \ r^3}[/tex]

[tex]\frac{ 3  \Delta r  }{  r}[/tex]

Using the values for the problem:

[tex]\frac{ 3 * 0.09 m  }{  5.66 m} = 0.0477[/tex]

This is, a percent uncertainty of 4.77 %