(New page: if a cord of length L is drawn... Let D be the distance from the center of the center of the circle to the cord. let the remaining distance to the edge of the circle be h. (such that r = ...)
 
 
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D = r*cos(.5*theta)
 
D = r*cos(.5*theta)
 +
 
D = .5*L*cot(.5*theta)
 
D = .5*L*cot(.5*theta)
 +
 
D = .5(4*r^2-L^2)^.5
 
D = .5(4*r^2-L^2)^.5
 
    
 
    
 +
 
L = 2*r*sin(.5*theta)
 
L = 2*r*sin(.5*theta)
 +
 
L = 2*D*tan(.5*theta)
 
L = 2*D*tan(.5*theta)
 +
 
L = 2*(r^2-D^2)^.5
 
L = 2*(r^2-D^2)^.5
 +
 
L = 2*[h*(2*r-h)]^.5
 
L = 2*[h*(2*r-h)]^.5
 +
  
 
now, any ideas on what comes next???
 
now, any ideas on what comes next???

Latest revision as of 06:08, 5 October 2008

if a cord of length L is drawn... Let D be the distance from the center of the center of the circle to the cord. let the remaining distance to the edge of the circle be h. (such that r = D + h)

To get started, i think we need to obtain the equations for D and L

let theta be the central angle.

D = r*cos(.5*theta)

D = .5*L*cot(.5*theta)

D = .5(4*r^2-L^2)^.5


L = 2*r*sin(.5*theta)

L = 2*D*tan(.5*theta)

L = 2*(r^2-D^2)^.5

L = 2*[h*(2*r-h)]^.5


now, any ideas on what comes next???

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