How we worked it out
Updated as you change the numbers.
- Angle θ in radians = degrees × π ÷ 180.
- Arc length = r × θ. Sector area = ½ × r² × θ. Chord = 2r × sin(θ ÷ 2).
Method and assumptions
A full circle is 2π radians, so the arc is the same fraction of the circumference as the angle is of 360°.
Questions
What is the arc length of a 60° arc with radius 10?
10.472 (10π ÷ 3). The sector area is 52.36 and the chord is exactly 10.
Sources
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