TEAMFLY
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Teach Yourself
Electricity and
Electronics
Third Edition
Stan Gibilisco
McGraw-Hill
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Contents
Preface xix
Part 1 Direct current
1 Basic physical concepts 3
Atoms 3
Protons, neutrons, and the atomic number 4
Isotopes and atomic weights 4
Electrons 5
Ions 5
Compounds 9
Molecules 10
Conductors 11
Insulators 11
Resistors 13
Semiconductors 14
Current 15
Static electricity 15
Electromotive force 16
Nonelectrical energy 18
Quiz 19
2 Electrical units 23
The volt 23
Current flow 24
The ampere 26
Resistance and the ohm 26
Conductance and the siemens 28
vii
Power and the watt 29
Energy and the watt hour 31

Resistance calculations 71
Power calculations 72
Resistances in series 73
Resistances in parallel 74
Division of power 75
Resistances in series-parallel 75
Resistive loads in general 77
Quiz 77
5 Direct-current circuit analysis 82
Current through series resistances 82
Voltages across series resistances 83
viii Contents
Voltage across parallel resistances 85
Currents through parallel resistances 86
Power distribution in series circuits 88
Power distribution in parallel circuits 88
Kirchhoff’s first law 89
Kirchhoff’s second law 91
Voltage divider networks 92
Quiz 95
6 Resistors 99
Purpose of the resistor 99
The carbon-composition resistor 102
The wirewound resistor 103
Film type resistors 104
Integrated-circuit resistors 104
The potentiometer 105
The decibel 107
The rheostat 109
Resistor values 110

The solenoid 144
The dc motor 145
Magnetic data storage 146
Quiz 149
Test: Part 1 153
Part 2 Alternating current
9 Alternating current basics 165
Definition of alternating current 165
Period and frequency 165
The sine wave 167
The square wave 167
Sawtooth waves 167
Complex and irregular waveforms 169
Frequency spectrum 170
Little bits of a cycle 172
Phase difference 173
Amplitude of alternating current 173
Superimposed direct current 175
The ac generator 176
Why ac? 178
Quiz 178
10 Inductance 183
The property of inductance 183
Practical inductors 184
The unit of inductance 185
Inductors in series 185
Inductors in parallel 186
Interaction among inductors 187
Effects of mutual inductance 188
Air-core coils 189


Sine waves as circular motion 217
Degrees of phase 218
Radians of phase 221
Phase coincidence 221
Phase opposition 222
Leading phase 222
Lagging phase 224
Vector diagrams of phase relationships 225
Quiz 226
13 Inductive reactance 231
Coils and direct current 231
Coils and alternating current 232
Reactance and frequency 233
Points in the RL plane 234
Vectors in the RL plane 235
Current lags voltage 237
Inductance and resistance 238
How much lag? 240
Quiz 243
Contents xi