15.2.7
The tube 1 rotates uniformly with angular velocity? = 2 rad / s around the axis AB. Inside the tube is moving the ball 2 mass m2 = 0,5 kg. The kinetic energy of the ball at the moment when, at a distance l = 0,5 m from the axis has a relative velocity vr = 0,2 m / s. (Reply 0.26)