The instrument can be used in the experiment of DC motor and AC / DC power generation experiment.1. In the motor experiment, change the current flow in the coil or the direction of the magnetic field to change the direction of rotation of the coil.At the same time, the red and blue LED lights on the sides of the coil, respectively indicate flowing in and out of the current direction of the coil, the coil is made of Φ2mm copper tube, coil frame size: 74x100 (±2mm).2, with the J0401 type demonstration meter, 100μA file, can do the generator experiment: (rotating coil to do DC power generation experiment, rotating magnetic field to do AC power generation experiment). 3, size: Φ180mmx235mm.