Electromagnetic combination

1. Content

The exhibition items consist of three experimental setups: electromagnetic accelerator, electric motor principle, and Ost test, demonstrating the relevant scientific principles of electromagnetics.

Electromagnetic Accelerator: Exhibition items enable the audience to understand the force and motion of charged objects in a magnetic field, as well as the principle of a cyclotron. When the sensor controlling the first coil senses that the ball is approaching the first coil, the first coil is immediately energized, and the iron ball is immediately attracted to pass through the first coil. When it passes through the first coil, the first coil immediately loses power, and the iron ball rolls towards the second coil due to inertia. When the sensor of the second coil senses the iron ball, the second coil is immediately energized to attract the iron ball to pass through the second coil. After passing through the coil, it rolls back to the next coil, and so on. When participating, the audience only needs to press a button to observe the movement of the ball.

Principle of electric motor: Before the audience participates in the interaction, the coil is first energized, and the current on the wire will generate a magnetic field. When it interacts with other magnetic fields around it, the wire will start to move under force. The audience holds the handle and slowly pushes the push rod forward to observe the change in the rotation speed of the turntable. When the audience adjusts the rod to change the distance between the magnet and the coil, the coil will deflect, and they will also find that the closer the magnet is to the coil, the faster the rotation speed of the coil. Electric motors are devices that convert electromagnetic energy into kinetic energy.

Auster test: composed of an electrified conductor and a small magnetic needle. Magnetic needles are distributed near conductors, and when the conductor is not electrified, small magnetic needles will point in the north-south direction of the Earth. When the conductor power supply is connected, current flows through the wire, which affects the magnetic needle and causes it to deflect. When participating, the audience only needs to press the start button to observe how the magnetic needle deflects.

2. Principle

The electromagnetic induction accelerator includes internal and external ring-shaped induction bodies, which are spaced apart from each other by a predetermined interval, and their inner and outer sides are arranged coaxially and parallel to induce an induced magnetic field along the axial direction. The channel is located between the internal and external loop inductors, including a dielectric layer in contact with the internal and external loop inductors, and secondary current is induced into the channel by the magnetic field between the dielectric layers. The discharge coil supplies pulse energy into the channel and generates plasma.

Motors are rotary electric machines that convert electrical energy into mechanical energy. An electric motor generates a rotating magnetic field through an energized coil and applies it to a squirrel cage shaped closed aluminum frame of the rotor to form a magnetic electric rotational torque. The electric motor is mainly composed of a stator and a rotor, and the direction of force movement of the energized wire in the magnetic field is related to the direction of the current and the direction of the magnetic field lines (magnetic field direction). The working principle of an electric motor is that the magnetic field exerts force on the current, causing the motor to rotate. Usually, the working part of an electric motor rotates, and this type of motor is called a rotor motor; There are also linear motors that perform linear motion.

The Oster experiment shows that there is a magnetic field around both the electrified wire and the permanent magnet. The Oster experiment revealed a very important essence - there is a magnetic field around the current, and the current is generated by the directional movement of charges, so the magnetic field around the electrified wire is essentially generated by the movement of charges. This phenomenon was first discovered by Danish physicist Oster through experiments in July 1820.

3. Purpose

This group of exhibitions consists of electromagnetic accelerator, electric motor principle, and Ost experiment. Through three electromagnetic experiment groups, it inspires young people's interest in science, enjoys the fun of education through entertainment, and inspires them to continuously climb the path of science.