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Guest Message by DevFuse

# Hole in a sphere

Best Answer bonanova, 23 August 2007 - 07:11 AM

The volume of the spherical caps is given by:
[list]
where
[list]
[*] h = the height of the cap (difference between r and the distance from the centre of the[/*:m:1cc31][list] sphere to the centre of the circular end of the hole)

Kudos to cpotting for the cap formula.
Spoiler for Here's the mathematical solution
Spoiler for Here's the logical solution
Go to the full post

166 replies to this topic

### #151 Brighterthan1000rocks

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Posted 22 October 2010 - 04:46 AM

Hole in a sphere has been a lot of fun for a long tim. But has anyone yet addressed the question regarding the minimum length of the drill?

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### #152 Sach

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Posted 22 October 2010 - 06:20 AM

Spoiler for Bononova, this isn't right.

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### #153 sridharang

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Posted 22 October 2010 - 09:52 AM

it's just the volume of the cylinder pi*r^2*"6 -4/3*pi*r^3
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### #154 aaronbcj

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Posted 22 October 2010 - 11:52 AM

What if the sphere already had a hole (of the same size of the drill) and you just re-drilled through it? Then the volume of sphere would remain same as before.
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### #155 bonanova

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Posted 24 October 2010 - 02:55 PM

What if the sphere already had a hole (of the same size of the drill) and you just re-drilled through it? Then the volume of sphere would remain same as before.

I guess the answer to that would be a sphere with a hole is not a sphere.

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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

### #156 bonanova

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Posted 24 October 2010 - 03:03 PM

Spoiler for Bononova, this isn't right.

Well, one could say vanishingly small and remove this objection.

For a short, tongue in cheek treatise on the existence of things with attributes of zero, read this.

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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

### #157 Andrew1258

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Posted 27 October 2010 - 07:08 AM

Spoiler for

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### #158 Barron

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Posted 27 October 2010 - 07:09 PM

Spoiler for well maybe

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### #159 bonanova

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Posted 28 October 2010 - 07:33 PM

Spoiler for well maybe

If the speaker were a sphere, sure ... good one.

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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

### #160 Tbone9

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Posted 30 November 2010 - 09:20 PM

Spoiler for

Spoiler for I'm with you...

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