A volume integral over a sphere

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SUMMARY

The discussion centers on evaluating the volume integral ∫∫∫∇·F dv over the sphere defined by x² + y² + z² ≤ 25, where F = (x² + y² + z²)(xi + yj + zk). The surface integral approach leads to the calculation of 125 * ∫∫ dσ, resulting in 12500π. However, the answer key indicates the result should be 100π, prompting the user to question the accuracy of their calculations and the answer key itself.

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Homework Statement



∫∫∫∇.Fdv over x2+y2+z2≤25

F= (x2+y2+z2)(xi+yj+zk)

Homework Equations



∫∫∫∇.Fdv = ∫∫ F.n dσ

n=∇g/|∇g|

The Attempt at a Solution



g(x,y,z)=x2+y2+z2-25

taking the surface integral and replacing all
(x2+y2+z2) with 25
i got
125 * ∫∫ dσ = 12500π

But the answer key says it is 100π
I think i am making a mistake with numbers but, i couldn't find what is wrong.

Thanks
 
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I don't think anything is wrong except the answer key.
 
Hmm, ok then, thanks.
 

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