Arc / Chord

Arc length, chord, and sagitta from radius plus central angle, chord, or sagitta.

Construction & Trades

Arc length, chord, and sagitta from radius plus central angle, chord, or sagitta.

App id: GEOM-06. Reference version 1.0.

How to fill it

Fill the inputs. The tool shows the outputs.

On the tool screen, Calc is the working sheet. Presets stores values you reuse. Reference is the formula, assumptions, and provenance below.

Formula

s = rθ; chord = 2r sin(θ/2); sagitta = r(1 − cos(θ/2))

Inputs

Name	Unit
Radius	`in`
Central angle (optional)	`deg`
Chord (optional)	`in`
Sagitta (optional)	`in`

Outputs

Name	Unit
Arc length (hero result)	`in`
Chord	`in`
Sagitta	`in`
Central angle	`deg`

Diagnose

This tool does not attach diagnose observations.

Provenance

Minor-arc formulas. Angle is the central angle.