Q. I also need a formula to find chord length if I know the radius and rise.
A. r = radius
c = chord length
central angle θ = 2·arcsin(c/(2r))
apothem d = r·cos(θ/2)
height h = r - d
-----
apothem d = r - h
θ = 2·arccos(d/r)
chord length c = 2r·sin(θ/2)
c = chord length
central angle θ = 2·arcsin(c/(2r))
apothem d = r·cos(θ/2)
height h = r - d
-----
apothem d = r - h
θ = 2·arccos(d/r)
chord length c = 2r·sin(θ/2)
What is the formula for calculating the radius of a circle when both the chord & height of the arc are known?
Q.
A. Let c be the chord length and h be the arc height. Draw a diagram. Draw two radii to make a triangle with the chord. Draw a third radius that divides that triangle into two smaller congruent right triangles. Then, by the Pythagorean Theorem:
(c/2)² + (r-h)² = r²
c²/4 + r² - 2rh + h² = r²
c²/4 + h² = 2rh
r = (c²/4 + h²)/(2h)
(c/2)² + (r-h)² = r²
c²/4 + r² - 2rh + h² = r²
c²/4 + h² = 2rh
r = (c²/4 + h²)/(2h)
what is the formula to find chord length between bolt holes when u know the diameter and number of holes?
Q.
A. This formula will work other than that it uses the radius of the bolt circle rather than the diameter:
s = 2r tan(Ï/n) Where:
s is the length of the side of the polygon or in our case the distance between the bolt holes.
r is the radius of the circle ( one half of the diameter)
Ï is of course pi â 3.14
n is the number of holes.
GL ⺠âº
s = 2r tan(Ï/n) Where:
s is the length of the side of the polygon or in our case the distance between the bolt holes.
r is the radius of the circle ( one half of the diameter)
Ï is of course pi â 3.14
n is the number of holes.
GL ⺠âº
Powered by Yahoo! Answers
No comments:
Post a Comment