Question

A disk spinning to the horizontal has a track from center to the edge. The disk spins at a constant speed. A marble is placed on the track near the center of the disk. The marble experiences an upward force and will eventually fly off the edge of the disk. When the marble goes off, will the direction be tangential, 45 degrees with respect to the tangential, or simply straight as if continuing the track in the air.

Answer 1

The marble flies off because the centripetal force (which is the force of friction )on it can no longer hold it in so it flies of in a straight line, i.e tangential to point where the marble is.