The arc length formula calculates the distance along a curved line, such as part of a circle's circumference. It is given by L = rθ, where L is the arc length, r is the radius, and θ is the central angle in radians. For degrees, convert to radians first.
Example: For a radius of 5 units and angle of 2 radians, L = 5 × 2 = 10 units.
