Basic Electrical Installation Work

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Good insulating materials are PVC, rubber, glass and wood. For each electron entering the positive terminal the battery, one will . Definition An insulator material which the outer electrons are tightly bound to the nucleus, there are free elec- trons move around the material.1(a).2 Symbols and Multiples for Use with Units Prefix Symbol Multiplication factor Mega 106 or 1,000,000 Kilo 103 or 1000 Hecto 102 or 100 Decca 10 Deci 101 or ÷10 Centi 102 or ÷100 Milli 103 or ÷1000 Micro 106 or ÷1,000,000 An insulator material which the outer electrons are tightly bound to the nucleus, there are free electrons move around the material. Definition A conductor material which the electrons are loosely bound the central nucleus and are, therefore, free to drift around the material random from one atom another, shown in Fig. 4. A conductor material which the electrons are loosely bound the central nucleus and are, therefore, free drift around the material ran- dom from one atom another, shown Fig.1(b), the free electrons drift purposefully one direction only. 4. The atom made central, posi- tively charged nucleus, surrounded negatively charged electrons. The electrical properties material depend largely upon how tightly these electrons are bound the central nucleus. Materials which are good conductors include copper, brass, aluminium and silver. (a) (b) Atoms Electron movement FIGURE 4. 4. The free electrons close to the positive plate the battery are attracted since unlike charges attract, and the free electrons near the negative plate will repelled from it.1(a). Good insulating materials are PVC, rubber, glass and wood. If battery attached conductor shown Fig.Basic electrotechnical units and theory 81 Basic circuit theory All matter made atoms which arrange themselves regular framework within the material. Table 4.1 Atoms and electrons material. Materials which are good conductors include copper, brass, alu- minium and silver