I don't know how many are familiar with this math club, I think it is mostly a southern thing, but here is a question which remains to stump me.(adsbygoogle = window.adsbygoogle || []).push({});

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Wire of 0.1cm is tightly wound (with no gaps in between layers) around a cylindrical pole of 3cm radius between heights of 0cm and 1cm. As a result, this part of the pole thickens, and the new radius is (4+h), where h is the height. How many centimeters of wire were used up?

(Hint: Length * Cross-sectional Area = Volume)

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Ok, here are my few thoughts.

I guess you need to find the volume and the cross-sectional area, and thus divide to find the length.

For volume, an inegral of something along of the lines of [tex]\pi\int_{0}^{1}(4+h)^2dh[/tex] might find the volume.

For cross-sectional area, perhaps (3)(4+h).

Thanks,

Jameson

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# Mu Alpha Theta Question

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