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Arc Length of a Circular Arc

An arc is a connected piece of a circle's boundary, and its arc length is the distance measured along that curve rather than straight across it. The arc cut off by a given fraction of a full turn is that same fraction of the circle's circumference, so arc length can be computed from the radius and the portion of the circle spanned. Arc length is a length, carrying the same units as the radius.

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Geometry: How to calculate arc length using radians in meters

The core principle establishes that arc length (S) is directly proportional to both the radius (r) and the central angle (θ), governed by the formula S = rθ where θ must be expressed in radians withi…