Welcome to OnlineConversion.com Forums

 OnlineConversion Forums Find the radius from a chord
 [ Home ] [ Forum Home ] Register FAQ Calendar Search Today's Posts Mark Forums Read

 Convert and Calculate Post any conversion related questions and discussions here. If you're having trouble converting something, this is where you should post.* Guest Posting is allowed.

#41
04-11-2010, 06:34 PM
 Unregistered Guest Posts: n/a
Re: Find the radius from a chord

hi, i have a problem.. looking back at the first page of this post , the circle image,

how do i find the radius of the circle? just by using the height which is m and the curved line arc length XZ
#42
04-11-2010, 06:36 PM
 Unregistered Guest Posts: n/a
Re: Find the radius from a chord

hi looking back to the first page circle image, how do i find the radius just by using
m and the curved line arc length XZ?
#43
04-12-2010, 02:55 AM
 JohnS Double Ultimate Supreme Member Join Date: Dec 2007 Location: SE Michigan, USA Posts: 8,708 Rep Power: 17
Re: Find the radius from a chord

Quote:
 Originally Posted by Unregistered hi looking back to the first page circle image, how do i find the radius just by using m and the curved line arc length XZ?
See post #27 which sets up the equation.
But you have to solve a transcendental equation by iterative methods.
#44
06-01-2010, 03:09 PM
 Unregistered Guest Posts: n/a
Re: Find the radius from a chord

C= chord in meters
m= middle height in meters (heightfrom chord to top of arc)

R=C^/8m + m/2

C=10
m=.25

R= 10^/8(.25) + .25/2
R= 100/2 + 0.125
R= 50 + 0.125
R= 50.125 m

good luck.
#45
08-23-2010, 11:17 PM
 Unregistered Guest Posts: n/a
Re: Find the radius from a chord

Hi,thanks for this useful info.

One point though, does anyone not read the entire thread before posting????

#46
09-04-2010, 05:54 PM
 Unregistered Guest Posts: n/a
Re: Find the radius from a chord

Quote:
 Originally Posted by Unregistered Yes that is correct. I know the length of the cord (c) and the height of the arc created by the cord (m). Is there a formula to find the radius with this information?
What is the formula?
#47
09-05-2010, 03:05 AM
 JohnS Double Ultimate Supreme Member Join Date: Dec 2007 Location: SE Michigan, USA Posts: 8,708 Rep Power: 17
Re: Find the radius from a chord

Quote:
 Originally Posted by Unregistered What is the formula?
See post #44 or numerous other posts in the thread.
#48
12-08-2010, 12:01 AM
 Unregistered Guest Posts: n/a
Re: Find the radius from a chord

Hi all!
I'm missing something that I have been looking at too long so I would appreciate some help
What if I know the Chord Length and the Radius or Diameter (Diameter of Corse being 2 * r)
I want to break it down into a usable example so here are some numbers to use
r = .625
c = .375
m = ?

Thanks!
#49
12-08-2010, 02:08 AM
 JohnS Double Ultimate Supreme Member Join Date: Dec 2007 Location: SE Michigan, USA Posts: 8,708 Rep Power: 17
Re: Find the radius from a chord

Quote:
 Originally Posted by Unregistered Hi all! I'm missing something that I have been looking at too long so I would appreciate some help What if I know the Chord Length and the Radius or Diameter (Diameter of Corse being 2 * r) I want to break it down into a usable example so here are some numbers to use r = .625 c = .375 m = ? Thanks!
From post #4
r = (m² + ¼c²)/2m

This results in the quadratic equation m² - 2*m*r + 0.25*c² =0, which has two solutions

m = r ± r*sqrt(1 - 0.25*c²/r²)

Normally, you want the solution with the minus sign. The chord divides a circle into two arcs, the first, less than 180°, has the m with the minus sign. The other piece of the circle, greater than 180°, the plus sign.

Last edited by JohnS; 12-09-2010 at 02:09 AM.
#50
12-08-2010, 11:04 PM
 Unregistered Guest Posts: n/a
Re: Find the radius from a chord

The answer using the above Numbers should be 0.0288

 Thread Tools Display Modes Linear Mode

 Posting Rules You may post new threads You may post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off Forum Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Main Forums     Convert and Calculate     Resources     General Chat

All times are GMT -8. The time now is 04:41 PM.