일반물리학 1 — Force and Motion-II: Problem 57

57 A puck of mass m = 1.50 kg slides in a circle of radius r = 25.0 cm on a frictionless table while attached to a hanging cylinder of mass M = 2.50 kg by means of a cord that extends through a hole in the table (Fig. 6-45). What speed keeps the cylinder at rest?