A giant rotating clock ride completes a \(5\pi/2\) radians swing. Each swing spans 40 meters along its arc. What is the radius of the circular path?

Solution

Solution: Arc length \(s=r\theta\), where the angle is measured in radians. Therefore, \(r=\frac{s}{\theta}=\frac{40}{5\pi/2}=\frac{16}{\pi}\) meters. Trick: For an angle in radians, radius equals arc length divided by the angle. Source note: Options C and D are mathematically equivalent; the PDF marks option C in green.