What is the relationship between the arc length and the radius of a circle when the central angle is defined in radians?

For a central angle measured in radians, the arc length is given by s = rθ, where r is the radius and θ is the angle. For a fixed angle, the arc length increases in direct proportion to the radius. Therefore, the best answer is “The length of the arc intercepted by the central angle is proportional to the radius of the circle.”

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