Page 8 - Teach Yourself Electricity and Electronics

viii Contents

Power and the watt 29
Energy and the watt hour 31
Other energy units 33
ac Waves and the hertz 34
Rectification and fluctuating direct current 35
Safety considerations in electrical work 37
Magnetism 38
Magnetic units 39
Quiz 40
3 Measuring devices 44
Electromagnetic deflection 44
Electrostatic deflection 46
Thermal heating 47
Ammeters 48
Voltmeters 49
Ohmmeters 51
Multimeters 53
FET and vacuum-tube voltmeters 54
Wattmeters 54
Watt-hour meters 55
Digital readout meters 56
Frequency counters 57
Other specialized meter types 57
Quiz 60
4 Basic dc circuits 65
Schematic symbols 65
Schematic diagrams 67
Wiring diagrams 68
Voltage/current/resistance circuit 68
Ohm’s Law 69
Current calculations 69
Voltage calculations 71
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