A ball, attached to the end of a horizontal cord, is revolved in a circle of radius 20 cm. The ball around 360o each second. Determine the magnitude of the centripetal acceleration! Known : Angular speed (Ο) = 360o/second = 1 revolution/second = 6,28 radians/second Radius (r) = 20 cm = 0,2 m Wanted : Centripetal acceleration (ar) Solution :