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Very Hard Question from SBHS EX1 Paper. (3 Viewers)

Carrotsticks

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I however do not agree with the solution. When you drill a hole through the middle, that removed volume is not merely a cylinder. It is a cylinder with small rounded ends representing the ends of the sphere.

This only works for very small values of c, where volume constituted by the rounded part is essentially negligible.
 
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^no shiit, that's why there's integration.

you take away the volumne of the inscribed cylinder first, then take away the top and bottom bit of the extra.

or you can take away a long cylinder then add back the extra you took away.

ps. if you disagree with the answer, something is wrong with u
 

hscishard

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^no shiit, that's why there's integration.

you take away the volumne of the inscribed cylinder first, then take away the top and bottom bit of the extra.

or you can take away a long cylinder then add back the extra you took away.

ps. if you disagree with the answer, something is wrong with u
Did she even do that?
That's prob his question.
 

nat_doc

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This.

From the working out, all I saw was V(sphere) - V(cylinder), which cannot be correct.
well if u only saw that, then i suggest reading it again.

i only integrated the volume of the sphere so that its a sphere that is missing sections from the top at bottom with a radius of c. hence this eliminates the need to remove the extra two sections from the ends as it wasn't there to start off with.
then u can easily remove the cylinder with no problems.
 

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