Induction is a process which takes place in many different ways in our everyday life. The physical basics of this proces

1. . . . . . . Induction Applications: Generator/RFID-Chips Magnetic materials There exist three different kinds of magnetic materials. The reason for magnetic qualities is the “Electron Configuration”, especially the sum of spins in the orbitals of each material. Diamagnetic materials (e.g. C, Ag, Bi) have full orbitals, so the sum of electron spins is 0. Such materials weaken an external magnetic field. Paramagnet materials(e.g. Al, Pt, Mn) have no full orbitals, so they have a spin, which interacts with outer fields. Such materials increase an external magnetic field. Ferromagnetic materials(e.g. Fe, Ni, Co) not only have their own electron spin, but also so called magnetic domains. Areas in which the magnetic moments of the atoms have the same direction. The domains dislocate themselves in a magnetic field, resulting in increasing it immense. Induction Cooker As seen in the picture above, the generator consists of a magnet (or coil) in the middle surrounded by other coils in an angle of 120°. When the magnet rotates, the magnetic flux in the coils is changed, producing a voltage looking like the one in the picture next to the generator. These generators have the advantage of not having slider contacts, which get broken due to friction. Generators of this kind are used in every kind of power plant, as emergency generators in hospitals and firms and as dynamos in bicycles. RFID-Chips(radio frequency identification) are composed of the emitter/receiver and the transponder. If the frequency of the emitters magnetic field is exactly the resonance frequency of the transponder, the chip inside the transponder sends out data to the receiver resulting in a signal. Such devices are primary used for identification systems. Depending on the frequency they use(between 125 kHz and 6 GHz) they have a range from 0,5m to 10m. They are used in debit/credit-cards, pet controls, product identification and even in vehicle controls(military). The advantage of the chips is that they are not effected by water or heat and are not easy to copy. Because of their compact size they can be used in even small products and are quite cheat. They just don´t work when they are surrounded by a metal sphere which works like a “Faraday Cage”. References http://en.wikipedia.org/wiki/Lenz%27s_law (from 07.06.2013 at 4:50 pm) http://www.bs-wiki.de/mediawiki/index.php?title=Drehstromgenerator:_Aufbau_und_Funktion (from 11.05.2013 at 2:30pm) https://upload.wikimedia.org/wikipedia/commons/b/b6/Eddy_currents_de.png (from 22.05.2013 at 6:18pm) http://www.leis-at-home.de/admin/news.php?id=1254485342 from 10.05.2013 at 3:32pm http://www.leis-at-home.de/admin/news.php?id=1254485342 from 10.05.2013 at 3:32pm Presentation from 9th July 2013 Edward Bickmann Induction in Daily Life A surprising application of induction is the induction cooker. Beneath the surface coils produce an alternating magnetic field in the pot above. The pot itself consists of ferromagnetic materials which direct the magnetic field ,making a better eddy current. Like in the eddy-current brake the pots basin gets hot and heats up the pots content(e.g. water). Unlike a general electric cooker, the plate on which the pot lays doesn´t have to be heated up, which means that lesser energy is needed to heat up the pot. The danger of burning oneself when handling with it is much lower than on other cookers. But induction cookers have some disadvantages. Not all pots are suitable for induction, especially when they do not consist of ferromagnetic materials and are commonly twice as expensive as electric cookers. Induction is a process which takes place in many different ways in our everyday life. The physical basics of this process are electric currents and magnetic fields. The magnetic flux which is defined as: Describes the amount of magnetic field lines through a certain area. If this flux is changed through time, an electric voltage is induced according to the “Faraday Induction Law”: The negative sign in the formula comes from another important aspect called “Lenz Law” which says:“An induced electromotive force (emf) always gives rise to a current whose magnetic field opposes the original change in magnetic flux.”