Electrified solenoid current magnetic field demonstrator

The utility model discloses an electrified solenoid current magnetic field demonstrator, which comprises a DC power supply and a current reversing switch and is characterized in that a master switch is connected between the DC power supply and the current reversing switch, the current reversing switch is connected with two ends of a solenoid, any two different positions on the solenoid are connected with a light-emitting diode a so as to form a circuit, the two different positions on the solenoid are also connected with a light-emitting diode b so as to form a circuit, the light-emitting diode a and the light-emitting diode b are connected in parallel and opposite in positive and negative electrode connection direction, and the internal part, the external part and two ends of the solenoid are provided with magnetic needles. The electrified solenoid current magnetic field demonstrator can demonstrate a relation between the current direction and the magnetic field direction and distribution characteristics of internal and external magnetic fields of the solenoid in physics teaching visually, simply and conveniently through a reasonable circuit design.