Basic Electrical Installation Work

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