At angular speed of 3 rev/s, the object moves a distance equal to 3 times the circumference of the circle each second, or a distance of 3 • 2π (1.20 cm) ≈ 22.6 cm.
So, with a linear speed of 22.6 cm/s = 0.226 m/s, the object has a centripetal acceleration a of
a = (0.226 m/s)² / (0.012 m) ≈ 18.8 m/s²
directed toward the center of the circle.
