Current i flows through a long wire. A square loop made of conducting wire held below the wire in the same vertical plane is released and allowed to fall under gravity. If acceleration of the loop is a, then :

Magnetic flux linked with the coil is inward and when the coil is falling inward flux is decreasing. According to Lenz's law induced current try to develop an outward flux so an anticlockwise current will flow in the coil. Now as the current in the wire and nearest part of the loop are in opposite direction a force of attraction acts and it falls with an acceleration less than g.