eddy current

By observing the falling speed of the magnetic disk, understand the eddy current. The exhibit mainly consists of magnetic interactive devices and disks made of different materials. Lower the discs of different materials from the top of the magnetic interactive device in sequence, and find that the plastic disc falls the fastest, followed by the copper disc, and the aluminum disc falls the slowest. Target audience: Adolescents aged 6-15. Display format: Electromechanical interactive device operation instructions (audience experience) 1 visitors press the button to power on the magnet device; 2. Take a disc from the booth and insert it into the slot of the electromagnet; When moving a metal disk in a strong magnetic field, a resistance force will be felt. Describe the electromagnetic characteristics and eddy current phenomena related to the internal connections between the storyline and exhibits.

Interaction type: Electromechanical interactive. The unit is designed for unsupervised public use: controls are recessed or shielded, moving parts are enclosed, and the interface is operable by a child of about six with no instruction. Where a screen is used, the language can be switched without changing the hardware, and the content can be replaced on site.

Eddy current is an induced current that flows along a closed circuit within a substance. The phenomenon of eddy currents was discovered by French physicist Leon Foucault in 1851. It is generated by a moving magnetic field intersecting with a metal conductor, or by a moving metal conductor intersecting perpendicularly with the magnetic field. In short, it is caused by the electromagnetic induction effect. This action generates a circulating current within the conductor. The faster the magnetic field changes, the greater the induced electromotive force and the stronger the eddy current; Eddy currents can cause conductors to generate heat. In devices where the magnetic field changes, the conductor is often divided into a group of insulated thin sheets or bundles of thin strips to reduce eddy current intensity and thus reduce energy loss; But when high temperatures need to be generated, eddy currents can also be used to obtain heat, such as the principle of high-frequency electric furnaces. When the current in the coil changes over time, due to electromagnetic induction, an induced current will be generated in another nearby coil.