When the magnet is allowed to fall vertically along the axis of the loop with its north pole towards the ring. The upper face of the ring will become the north pole in an attempt to oppose the approaching north pole of the magnet. Therefore the acceleration in the magnet is less than g.
Note: If the coil is broken at any point then induced emf will be generated in it but no induced current will flow. In this condition, the coil will not oppose the motion of the magnet and the magnet will fall freely with acceleration g. (i.e. a = g)
Check out the video given below to know more about magnetic field and field lines