Basic Electrical Installation Work

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Silver and nickel plating has long been used enhance the appearance cutlery, candlesticks and sporting trophies. Electrolysis industrial process used the refining metals and elec- troplating. Small pieces of lodestone attached wooden splints floating bowl water always came rest pointing north–south direction. Magnetism The Greeks knew early 600 that certain form iron ore, now known magnetite lodestone, had the property attracting small pieces iron. Later, during the Middle Ages, navigational compasses were made using the magnetic properties lodestone. When load connected across the anode and cathode, current drawn from this arrangement, which is called cell. has many use- ful applications providing portable electrical power, but electrochemical action can also undesirable since the basis electrochemical cor- rosion which rots our motor cars, industrial containers and bridges. battery made number cells. An anode and cathode dissimilar metal placed electrolyte can react chemically and produce emf. Lines magnetic flux have physical existence, but they were introduced Michael Faraday (1791–1867) way explaining the magnetic energy existing space material. The symbol used for magnetic flux the Greek letter (phi) and the unit magnetic flux the weber (symbol Wb), pronounced ‘veber’, commemorate the work the German physicist Wilhelm Weber (1804–1891). was one the earliest industrial applications electric cur- rent. Iron, nickel and cobalt are the only elements which are attracted strongly by magnet. Most the aluminium produced today extracted from its ore by electrochemical methods.Basic Electrical Installation Work 112 CHEMICAL EFFECT When electric current flows through conducting liquid, the liquid is separated into its chemical parts. The word lodestone is derived from old English word meaning ‘the way’, and the word mag- netism derived from Magnesia, the place where magnetic ore was first discovered. 2. . The conductors which make contact with the liquid are called the anode and cathode. Electroplating serves double purpose pro- tecting base metal from atmospheric erosion and also giving more expensive and attractive appearance. They help us to visualize and explain the magnetic effects. These materials are said ferromagnetic. Lines magnetic flux always form closed loops. Copper, brass, wood, PVC and glass are not attracted magnet and are, therefore, described non-magnetic. The liquid itself called the electrolyte, and the process called electrolysis. Some basic rules magnetism 1