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Electrical engineering know it all
[...]... University and MSEE from Duke University w ww n e w n e s p r e s s c om About the Authors xvii Michael Laughton BASc, (Toronto), PhD (London), DSc (Eng.) (London), FREng, FIEE, CEng (Chapters 25) is the editor of Electrical Engineer’s Reference Book, 16th Edition He is the Emeritus Professor of Electrical Engineering of the University of London and former Dean of Engineering of the University and... d’Unités (International system of units), usually abbreviated to SI units, and is based on the metric system This was introduced in 1960 and is now adopted by the majority of countries as the official system of measurement The basic units in the SI system are listed with their symbols, in Table 1.1 Derived SI units use combinations of basic units and there are many of them Two examples are: ● ● Velocity—meters... taken from the supply is 4 A 1.9 Summary of Terms, Units and Their Symbols Table 1.3: Electrical terms, units, and symbols Quantity Quantity Symbol Unit Unit symbol Length l meter m Mass m kilogram kg Time t second s Velocity v meters per second m/s or m sϪ1 Acceleration a meters per second squared m/s2 or m sϪ2 Force F newton N Electrical charge or quantity Q coulomb C Electric current I ampere A Resistance... flowing through it when 1 volt is connected across it, i.e., resistance R ϭ potential difference current 1.13 Basic Electrical Measuring Instruments An ammeter is an instrument used to measure current and must be connected in series with the circuit Figure 1.2 shows an ammeter connected in series with the lamp to measure the current flowing through it Since all the current in the circuit passes through... in Electrical Engineering from the University of Jordan in 1984 and the MSc and PhD degrees, from the University of Manchester Institute of Science and Technology (UMIST), in 1986 and 1991, respectively He worked as a research Fellow at the University of Wales-Bangor—U.K from 1990 till 1993, researching very high speed optical systems and circuits He was a Senior Lecturer in Optoelectronic Circuits... electric circuit when a current of one ampere is maintained for one second Thus, charge, in coulombs Q ϭ It where I is the current in amperes and t is the time in seconds Example 1.1 If a current of 5 A flows for 2 minutes, find the quantity of electricity transferred Solution Quantity of electricity Q ϭ It coulombs I ϭ 5 A, t ϭ 2 ϫ 60 ϭ 120 s Hence, Q ϭ 5 ϫ 120 ϭ 600 C 1.3 Force The unit of force is... G ϭ ϭ Sϭ S ϭ 10 S 100 R 100 ϫ 10Ϫ3 (b) G ϭ 1.8 Electrical Power and Energy When a direct current of I amperes is flowing in an electric circuit and the voltage across the circuit is V volts, then, power, in watts P ϭ VI Electrical energy ϭ Power ϫ time ϭ VIt joules Although the unit of energy is the joule, when dealing with large amounts of energy, the unit used is the kilowatt hour (kWh) where 1 kWh... the author of Electronics Circuits He is the former Director of Learning Technology at Brooklands College, Surrey, U.K Douglas Warne (Chapters 25) is the editor of Electrical Engineers Reference book, 16th Edition Warne graduated from Imperial College London in 1967 with a 1st class honours degree in electrical engineering, during this time he had a student apprenticeship with AEI Heavy Plant Division,... common ones are shown in Figure 1.1 1.11 Electric Current and Quantity of Electricity All atoms consist of protons, neutrons and electrons The protons, which have positive electrical charges, and the neutrons, which have no electrical charge, are contained within the nucleus Removed from the nucleus are minute negatively charged particles called electrons Atoms of different materials differ from one another... quantity of electricity transferred Solution Quantity of electricity, Q ϭ It coulombs I ϭ 10 A; t ϭ 4 ϫ 60 ϭ 240 s Hence, Q ϭ 10 ϫ 240 ϭ 2400 C 1.12 Potential Difference and Resistance For a continuous current to flow between two points in a circuit a potential difference or voltage, V, is required between them; a complete conducting path is necessary to and from the source of electrical energy The unit . alt="" Electrical Engineering Newnes Know It All Series PIC Microcontrollers: Know It All Lucio Di Jasio, Tim Wilmshurst, Dogan Ibrahim, John Morton, Martin Bates, Jack Smith, D.W. Smith, and. 25) is the editor of Electrical Engineer’s Reference Book, 16 th Edition . He is the Emeritus Professor of Electrical Engineering of the University of London and former Dean of Engineering of. 978-0-7506-8581-8 Electrical Engineering: Know It All Clive Maxfi eld, Alan Bensky, John Bird, W. Bolton, Izzat Darwazeh, Walt Kester, M.A. Laughton, Andrew Leven, Luis Moura, Ron Schmitt, Keith Sueker,