Basic Electrical Installation Work

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