The wall of the container exerts a normal contact force on the ball bearing, thus pushing the ball bearing in the centripetal direction. This causes the ball bearing’s velocity to keep changing its direction towards the centre of the circle, resulting in circular motion.
When the centripetal force is removed (when container is lifted), the ball bearing continues at its current velocity (as according to Newton’s 1st Law), which is in the tangential direction.
xmPhysics 