In this case we have a circular movement problem. By definition, the linear velocity in a circular motion is given by v = w * r where w: rotational speed. r: radio. We have then that the speed is given by v = (1200 rev / min * ((2 * pi rad) / (1 rev)) * ((1 min) / (60 s))) * ((15/2 cm) * (1 m / 100 cm) ) = 9.42 m / s answer the speed is 9.42 m / s