Summary Physics Ncert 12th part 1

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I

, CONTENTS


FOREWORD v
PREFACE xi

CHAPTER ONE
ELECTRIC CHARGES AND FIELDS
1.1 Introduction 1
1.2 Electric Charges 1
1.3 Conductors and Insulators 5
1.4 Charging by Induction 6
1.5 Basic Properties of Electric Charge 8
1.6 Coulomb’s Law 10
1.7 Forces between Multiple Charges 15
1.8 Electric Field 18
1.9 Electric Field Lines 23
1.10 Electric Flux 25
1.11 Electric Dipole 27
1.12 Dipole in a Uniform External Field 31
1.13 Continuous Charge Distribution 32
1.14 Gauss’s Law 33
1.15 Application of Gauss’s Law 37

CHAPTER TWO
ELECTROSTATIC POTENTIAL AND CAPACITANCE
2.1 Introduction 51
2.2 Electrostatic Potential 53
2.3 Potential due to a Point Charge 54
2.4 Potential due to an Electric Dipole 55
2.5 Potential due to a System of Charges 57
2.6 Equipotential Surfaces 60
2.7 Potential Energy of a System of Charges 61
2.8 Potential Energy in an External Field 64
2.9 Electrostatics of Conductors 67
2.10 Dielectrics and Polarisation 71
2.11 Capacitors and Capacitance 73
2.12 The Parallel Plate Capacitor 74
2.13 Effect of Dielectric on Capacitance 75

,2.14 Combination of Capacitors 78
2.15 Energy Stored in a Capacitor 80
2.16 Van de Graaff Generator 83

CHAPTER THREE
CURRENT ELECTRICITY
3.1 Introduction 93
3.2 Electric Current 93
3.3 Electric Currents in Conductors 94
3.4 Ohm’s law 95
3.5 Drift of Electrons and the Origin of Resistivity 97
3.6 Limitations of Ohm’s Law 101
3.7 Resistivity of various Materials 101
3.8 Temperature Dependence of Resistivity 103
3.9 Electrical Energy, Power 105
3.10 Combination of Resistors — Series and Parallel 107
3.11 Cells, emf, Internal Resistance 110
3.12 Cells in Series and in Parallel 113
3.13 Kirchhoff’s Laws 115
3.14 Wheatstone Bridge 118
3.15 Meter Bridge 120
3.16 Potentiometer 122

CHAPTER FOUR
MOVING CHARGES AND MAGNETISM
4.1 Introduction 132
4.2 Magnetic Force 133
4.3 Motion in a Magnetic Field 137
4.4 Motion in Combined Electric and Magnetic Fields 140
4.5 Magnetic Field due to a Current Element, Biot-Savart Law 143
4.6 Magnetic Field on the Axis of a Circular Current Loop 145
4.7 Ampere’s Circuital Law 147
4.8 The Solenoid and the Toroid 150
4.9 Force between Two Parallel Currents, the Ampere 154
4.10 Torque on Current Loop, Magnetic Dipole 157
4.11 The Moving Coil Galvanometer 163

CHAPTER FIVE
MAGNETISM AND MATTER
5.1 Introduction 173
5.2 The Bar Magnet 174
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, 5.3 Magnetism and Gauss’s Law 181
5.4 The Earth’s Magnetism 185
5.5 Magnetisation and Magnetic Intensity 189
5.6 Magnetic Properties of Materials 191
5.7 Permanent Magnets and Electromagnets 195

CHAPTER SIX
ELECTROMAGNETIC INDUCTION
6.1 Introduction 204
6.2 The Experiments of Faraday and Henry 205
6.3 Magnetic Flux 206
6.4 Faraday’s Law of Induction 207
6.5 Lenz’s Law and Conservation of Energy 210
6.6 Motional Electromotive Force 212
6.7 Energy Consideration: A Quantitative Study 215
6.8 Eddy Currents 218
6.9 Inductance 219
6.10 AC Generator 224

CHAPTER SEVEN
ALTERNATING CURRENT
7.1 Introduction 233
7.2 AC Voltage Applied to a Resistor 234
7.3 Representation of AC Current and Voltage by
Rotating Vectors — Phasors 237
7.4 AC Voltage Applied to an Inductor 237
7.5 AC Voltage Applied to a Capacitor 241
7.6 AC Voltage Applied to a Series LCR Circuit 244
7.7 Power in AC Circuit: The Power Factor 252
7.8 LC Oscillations 255
7.9 Transformers 259

CHAPTER EIGHT
ELECTROMAGNETIC WAVES
8.1 Introduction 269
8.2 Displacement Current 270
8.3 Electromagnetic Waves 274
8.4 Electromagnetic Spectrum 280

ANSWERS 288



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