Got math? Or do I need a 40' string?

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Dave Bagwill
Posts: 5952
Joined: Tue Dec 13, 2011 7:44 pm

Got math? Or do I need a 40' string?

Post by Dave Bagwill » Thu Feb 23, 2012 9:59 pm

Please see the incredibly detailed CAD drawing attached, done on my Cray supercomputer out in the barn.

Given the centerpoint on the top of the piece of wood - the long rectangle - and given that we have a 40' radius arc from that point to point 'a', how can we calculate the distance 'x' and the point 'b' on the top of the board?
arc.png
arc.png (16.3 KiB) Viewed 222 times



I'm looking for the sagitta of the arc, to be more precise.
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Tim Benware
Posts: 1489
Joined: Thu Dec 22, 2011 1:22 pm
Location: Asheboro, NC

Re: Got math? Or do I need a 40' string?

Post by Tim Benware » Thu Feb 23, 2012 11:05 pm

deadedith wrote:Please see the incredibly detailed CAD drawing attached, done on my Cray supercomputer out in the barn.

Given the centerpoint on the top of the piece of wood - the long rectangle - and given that we have a 40' radius arc from that point to point 'a', how can we calculate the distance 'x' and the point 'b' on the top of the board?
arc.png



I'm looking for the sagitta of the arc, to be more precise.
Is this what you're looking for?

http://liutaiomottola.com/formulae/sag.htm
I've "Ben-Had" again!
Tim Benware
Creedmoor, NC

Dave Bagwill
Posts: 5952
Joined: Tue Dec 13, 2011 7:44 pm

Re: Got math? Or do I need a 40' string?

Post by Dave Bagwill » Fri Feb 24, 2012 2:23 am

Dang - (slapping my forehead) - I like that guy's site a lot and just plain forgot about his formulae.
That is exactly what I was looking for and as a reward for finding it I hereby name you, TimB - THE MAN.

Thanks.
-Under permanent construction

Tim Benware
Posts: 1489
Joined: Thu Dec 22, 2011 1:22 pm
Location: Asheboro, NC

Re: Got math? Or do I need a 40' string?

Post by Tim Benware » Fri Feb 24, 2012 9:12 am

deadedith wrote:Dang - (slapping my forehead) - I like that guy's site a lot and just plain forgot about his formulae.
That is exactly what I was looking for and as a reward for finding it I hereby name you, TimB - THE MAN.

Thanks.
WooWhooo!!!
I've "Ben-Had" again!
Tim Benware
Creedmoor, NC

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