When the magnetic flux of the coil circuit changes, an induced electromotive force is generated in the coil, and an induced current is generated in the loop (the induced electromotive force generated by the change of the magnetic flux passing through the coil. Today, we talk about the eddy current effect in the electromagnetic induction. The reasons and advantages and disadvantages and control. If a conductor is placed in a changing magnetic field or moved relative to a magnetic field, since the inside of the conductor can form a closed loop, the magnetic flux passing through the loop changes, so an induced current is also generated in the conductor. The body closes itself into a spiral shape, so it is called eddy current, referred to as eddy current. As shown in the figure (a) on the right, the eddy current is generally large due to the small conductor resistance. Due to the thermal effects of the current, eddy currents cause the conductor to heat up and consume energy, so eddy currents are sometimes detrimental. For example, through the alternating current magnetic field in the transformer, the motor and the generator, the core will generate eddy current, and the eddy current is the iron core heating, which causes loss (commonly known as iron loss) and causes the device to generate heat, the temperature rises, and the insulating material is prone to aging. Shorten the service life of transformers, motors and generators and even damage them. Eddy currents are detrimental in various motors and transformers, but they are also useful. For example, high-frequency induction furnaces often used in factory smelting alloys use eddy currents generated in metal conductor blocks to melt metal. Electrical measuring instruments require that the swing of the pointer be quickly stopped to quickly read the readings (such as ammeters, voltmeters, etc.). In order to achieve this, the coil of the ammeter is wound around the aluminum frame. When the current to be measured passes through the coil, the coil drives the pointer and the aluminum frame to rotate together. When the aluminum frame rotates in the magnetic field, an eddy current is generated, and the magnetic field hinders the force of the eddy current. Their swing, so the pointer quickly stabilized to the reading position, which is the application of the eddy current effect - electromagnetic damping. Electrical damping is also commonly used in electromagnetic brakes for electric locomotives. As shown in the right picture (b) and the right picture here, in order to reduce the eddy current loss, in the core material of the motor, generator, transformer, AC electromagnet, etc., the whole core is not used, but A piece of silicon steel sheet coated with an insulating varnish is laminated. This is because silicon steel contains 2 to 5% of silicon, which can increase the electrical resistivity of the iron core. In addition, the iron piece and the iron piece are insulated from each other, so that the eddy current is confined between the narrow sheets, and the resistance of the circuit is large, and the eddy current is large. It is greatly reduced, so that the existence of eddy currents is greatly reduced.
Product catagories of stylus pen for ipad, which is just for iPad Versions 2018 & 2019 and above.
It can work on following:
iPad 6th 2018: A1893/A1954
Stylus Pen For Ipad,Stylus Pen,Stylus Pen For Drawing,Touch Pencil Shenzhen Ruidian Technology CO., Ltd , https://www.wisonens.com
iPad 7th 2019: A2197/A2198/A2200
iPad 8th 2020: A2270/A2428/A2429/A2430
iPad air 3rd: A2152/A2153/A2154/A2123
iPad Air 4th: A2072/A2316/A2324/2325
iPad mini 5th: A2124/A2125/A2126/A2133
iPad Pro 1st/2nd 11: A1980/A2013/A1934/A1979/A2228/A2068/A2230/A2231
iPad Pro 3rd/4th 12.9: A2069/A2229/A2233/A2232/A1876/A2014/A1895/A1983