Engineering Physics

640 Pages·2013·6.601 MB·English

by  Naidu, S. Mani

ENGINEERING
PHYSICS
Dr S. Mani Naidu
M.Sc., Ph.D., P.G.D.C.A.
Associate Professor of Physics
Sree Vidyanikethan Engineering College
Tirupati, Andhra Pradesh
Copyright © 2013 Dorling Kindersley (India) Pvt. Ltd.
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ISBN 9788131761632(cid:13)(cid:10)
eISBN 9789332514126(cid:13)(cid:10)

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Brief Contents
Preface xv
Chapter 1 Bonding in Solids 1-1
Chapter 2 Crystal Structures 2-1
Chapter 3 Crystal Planes, X-ray Diffraction
and Defects in Solids 3-1
Chapter 4 Elements of Statistical Mechanics and
Principles of Quantum Mechanics 4-1
Chapter 5 Electron Theory of Metals 5-1
Chapter 6 Dielectric Properties 6-1
Chapter 7 Magnetic Properties 7-1
Chapter 8 Semiconductors and Physics of
Semiconductor Devices 8-1
Chapter 9 Superconductivity 9-1
Chapter 10 Lasers 10-1
Chapter 11 Fibre Optics 11-1
Chapter 12 Holography 12-1
Chapter 13 Acoustics of Buildings and Acoustic
Quieting 13-1
iv Brief Contents
Chapter 14 Nanotechnology 14-1
Chapter 15 Optics 15-1
Chapter 16 Non-destructive Testing Using
Ultrasonics 16-1
Chapter 17 Nuclear Physics 17-1
Chapter 18 Electromagnetic Waves 18-1
Chapter 19 Special theory of Relativity:
Relativistic Mechanics 19-1
Index I-1
Contents
 Preface xv
Chapter 1 Bonding in Solids 1-1
1.1 Different types of bonding in solids 1-1
1.2 Cohesive energy and estimation of cohesive
energy of ionic solids 1-4
1.3. Estimation of cohesive energy of NaCl molecule
in a solid 1-8
1.4 Madelung constant 1-9
Formulae 1-10
Solved Problems 1-11
Multiple-choice Questions 1-14
Answers 1-16
Review Questions 1-16
Chapter 2 Crystal Structures 2-1
2.1 Introduction 2-1
2.2 Space lattice (or) crystal lattice 2-2
2.3 The basis and crystal structure 2-3
2.4 Unit cell and lattice parameters 2-3
2.5 Crystal systems and Bravais lattices 2-4
2.6 Structure and packing fractions of simple cubic
[SC] structure 2-9
2.7 Structure and packing fractions of body-centred
cubic structure [BCC] 2-10
2.8 Structure and packing fractions of face-centred
cubic [FCC] structure 2-11
2.9 Diamond cubic structure 2-12
2.10 NaCl crystal structure 2-13
vi Contents
2.11 Caesium chloride [CsCl] structure 2-14
2.12 Zinc sulphide [ZnS] structure 2-14
2.13 Stacking sequence in metallic crystals 2-15
2.14 Calculation of lattice constant 2-16
Solved Problems 2-17
Multiple-choice Questions 2-19
Answers 2-22
Review Questions 2-22
Chapter 3 C rystal Planes, X-ray Diffraction
and Defects in Solids 3-1
3.1 Crystal planes, directions and Miller indices 3-1
3.2 Distance of separation between
successive hkl planes 3-4
3.3 Imperfections in crystals 3-7
3.4 Energy for the formation of a vacancy and number
of vacancies — at equilibrium concentration 3-11
3.5 Diffraction of X-rays by crystal planes and
Bragg’s law 3-15
3.6 Powder method 3-17
3.7 Laue method 3-18
Formulae 3-19
Solved Problems 3-20
Multiple-choice Questions 3-27
Answers 3-32
Review Questions 3-32
Chapter 4 E lements of Statistical Mechanics and
Principles of Quantum Mechanics 4-1
4.1 Introduction 4-1
4.2 Phase space 4-1
4.3 Maxwell–Boltzmann distribution 4-1
4.4 Fermi–Dirac distribution 4-3
4.5 Bose–Einstein distribution 4-5
4.6 Comparison of Maxwell–Boltzmann,
Fermi–Dirac and Bose–Einstein distributions 4-7
4.7 Photon gas 4-7
4.8 Concept of electron gas and Fermi energy 4-8
4.9 Density of electron states 4-8
4.10 Black body radiation 4-11
4.11 Waves and particles—de Broglie
hypothesis—Matter waves 4-12
Contents vii
4.12 Relativistic correction 4-15
4.13 Planck’s quantum theory of black body
radiation 4-18
4.14 Experimental study of matter waves 4-19
4.14 Schrödinger’s time-independent wave equation 4-26
4.15 Heisenberg uncertainty principle 4-29
4.16 Physical significance of the wave function 4-31
4.17 Particle in a potential box 4-32
Formulae 4-41
Solved Problems 4-42
Multiple-choice Questions 4-48
Answers 4-53
Review Questions 4-53
Chapter 5 Electron Theory of Metals 5-1
5.1 Introduction 5-1
5.2 Classical free electron theory of metals 5-2
5.3 Relaxation time, mean free path, mean collision
time and drift velocity 5-5
5.4 Fermi-Dirac distribution 5-7
5.5 Quantum free electron theory of electrical
conduction 5-9
5.6 Sources of electrical resistance 5-11
5.7 Band theory of solids 5-12
5.8 Bloch theorem 5-20
5.9 Origin of energy bands formation in solids 5-22
5.10 Velocity and effective mass of an electron 5-22
5.11 Distinction between metals, semiconductors and
insulators 5-25
Formulae 5-28
Solved Problems 5-28
Multiple-choice Questions 5-36
Answers 5-39
Review Questions 5-40
Chapter 6 Dielectric Properties 6-1
6.1 Introduction 6-1
6.2 Dielectric constant 6-1
6.3 Internal or local field 6-2
6.4 Clausius–Mosotti relation 6-4
6.5 Orientational, ionic and electronic polarizations 6-7
viii Contents
6.6 Frequency dependence of polarizability:
(Dielectrics in alternating fields) 6-12
6.7 Piezoelectricity 6-17
6.8 Ferroelectricity 6-18
6.9 Frequency dependence of dielectric constant 6-20
6.10 Important requirements of insulators 6-22
Formulae 6-23
Solved Problems 6-24
Multiple-choice Questions 6-29
Answers 6-34
Review Questions 6-34
Chapter 7 Magnetic Properties 7-1
7.1 Magnetic permeability 7-1
7.2 Magnetization (M ) 7-2
7.3 Origin of magnetic moment—Bohr
magneton—electron spin 7-2
7.4 Classification of magnetic materials 7-5
7.5 Classical theory of diamagnetism
[Langevin theory] 7-7
7.6 Theory of paramagnetism 7-9
7.7 Domain theory of ferromagnetism 7-12
7.8 Hysteresis curve 7-17
7.9 Anti-ferromagnetic substances 7-18
7.10 Ferrimagnetic substances [Ferrites] 7-20
7.11 Soft and hard magnetic materials 7-20
7.12 Applications of ferrites 7-22
Formulae 7-23
Solved Problems 7-23
Multiple-choice Questions 7-26
Answers 7-30
Review Questions 7-31
Chapter 8 S emiconductors and Physics of
Semiconductor Devices 8-1
8.1 Introduction 8-1
8.2 Intrinsic semiconductors—carrier concentration 8-1
8.3 Electrical conductivity of a semiconductor 8-11
8.4 Extrinsic semiconductors 8-15
8.5 Carrier concentration in extrinsic
semiconductors 8-18
Contents ix
8.6 Minority carrier life time 8-21
8.7 Drift and diffusion currents 8-23
8.8 Einstein’s relations 8-26
8.9 Continuity equation 8-27
8.10 Hall effect 8-31
8.11 Direct and indirect band gap semiconductors 8-33
8.12 Formation of p-n junction 8-35
8.13 Energy band diagram of p-n diode 8-38
8.14 Diode equation 8-39
8.15 p-n junction biasing 8-40
8.16 V–I characteristics of p-n diode 8-42
8.17 p-n diode rectifier 8-44
8.18 Light emitting diode [LED] 8-49
8.19 Liquid crystal display (LCD) 8-52
8.20 Photodiodes 8-54
Formulae 8-57
Solved Problems 8-59
Multiple-choice Questions 8-66
Answers 8-72
Review Questions 8-73
Chapter 9 Superconductivity 9-1
9.1 Introduction 9-1
9.2 General features of superconductors 9-3
9.3 Type-I and Type-II superconductors 9-8
9.4 Penetration depth 9-9
9.5 Flux quantization 9-11
9.6 Quantum tunnelling 9-12
9.7 Josephson’s effect 9-14
9.8 BCS theor y 9-16
9.9 Applications of superconductivity 9-19
Formulae 9-23
Solved Problems 9-23
Multiple-choice Questions 9-25
Answers 9-29
Review Questions 9-29
Chapter 10 Lasers 10-1
10.1 Introduction 10-1
10.2 Characteristics of laser radiation 10-1