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The book only briefly covers this section and there is an example with a sphere, but I dont really know how to get started.

Heres what I tried:

I basically cut the upper region up into three rectangles, two of them having negative area:

triangle 1)[tex]A=240(100)=24000mm^2[/tex]

[tex]\bar{y}=250mm[/tex]

Distance travelled by C [tex]2\pi(250)=1571mm[/tex]

Volume = [tex]1571mm(24000mm^2=37704000mm^3[/tex]

And then the same thing was done for the other two rectangles of negative area, and then a total volume was found. From this I found a mass which I think is wrong.

Is this the right approach?

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# Homework Help: Pappus-Guldinus Theorem

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