Applied Physics

509 Pages·2009·4.157 MB·English

by  S. Mani Naidu

A text book of
APPLIED PHYSICS
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A text book of
APPLIED 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
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ISBN 9788131724958
eISBN 9789332500846

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Contents
Foreword xiv
Preface xv
Acknowledgements xvi
Road Map to the Syllabus – JNTU Hyderabad xvii
Chapter 1 Bonding in Solids 1.1
1.1 Diff erent 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 Th e basis and crystal structure 2.3
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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 2.8
2.7 Structure and packing fractions of body-centred
cubic structure [BCC] 2.9
2.8 Structure and packing fractions of face-centred
cubic [FCC] structure 2.10
2.9 Diamond cubic structure 2.11
2.10 NaCl crystal structure 2.12
2.11 Caesium chloride [CsCl] structure 2.13
2.12 Zinc sulphide [ZnS] structure 2.14
2.13 Stacking sequence in metallic crystals 2.14
2.14 Calculation of lattice constant 2.15
Solved Problems 2.16
Multiple Choice Questions 2.18
Answers 2.21
Review Questions 2.21
Chapter 3 Crystal 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 euqilibrium
concentration 3.10
3.5 Diff raction of X-rays by crystal planes and
Bragg’s law 3.14
3.6 Powder Method 3.16
3.7 Laue Method 3.17
Formulae 3.18
Solved Problems 3.19
Multiple Choice Questions 3.25
Answers 3.30
Review Questions 3.31
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Contents
Chapter 4 Elements 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 4.7
4.9 Density of electron states 4.8
4.10 Black body radiation 4.10
4.11 Waves and particles—de Broglie hypothesis—
Matter waves 4.12
4.12 Relativistic correction 4.14
4.13 Planck’s quantum theory of black body radiation 4.17
4.14 Experimental study of matter waves 4.19
4.14 Schrödinger’s time-independent wave equation 4.25
4.15 Heisenberg uncertainty principle 4.28
4.16 Physical signifi cance of the wave function 4.30
4.17 Particle in a potential box 4.31
Formulae 4.39
Solved Problems 4.41
Multiple Choice Questions 4.46
Answers 4.51
Review Questions 4.51
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 5.8
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5.6 Sources of electrical resistance 5.11
5.7 Band theory of solids 5.12
5.8 Bloch theorem 5.19
5.9 Origin of energy bands formation in solids 5.21
5.10 Velocity and eff ective mass of an electron 5.21
5.11 Distinction between metals, semiconductors
and insulators 5.24
Formulae 5.26
Solved Problems 5.27
Multiple Choice Questions 5.34
Answers 5.38
Review Questions 5.38
Chapter 6 Dielectric Properties 6.1
6.1 Introduction 6.1
6.2 Dielectric constant 6.1
6.3 Internal or local fi eld 6.2
6.4 Clausius–Mosotti relation 6.4
6.5 Orientational, ionic and electronic polarizations 6.7
6.6 Frequency dependence of polarizability:
[Dielectrics in alternating fi elds] 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 6.21
Formulae 6.23
Solved Problems 6.23
Multiple Choice Questions 6.29
Answers 6.33
Review Questions 6.33
Chapter 7 Magnetic Properties 7.1
7.1 Magnetic permeability 7.1
7.2 Magnetization (M ) 7.2
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7.3 Origin of magnetic moment – Bohr
magneton – electron spin 7.2
7.4 Classifi cation of magnetic materials 7.5
7.5 Classical theory of diamagnetism
(Langevin theory) 7.6
7.6 Th eory of paramagnetism 7.9
7.7 Domain theory of ferromagnetism 7.12
7.8 Hysteresis curve 7.16
7.9 Anti-ferromagnetic substances 7.17
7.10 Ferrimagnetic substances [Ferrites] 7.19
7.11 Soft and hard magnetic materials 7.20
7.12 Applications of ferrites 7.21
Formulae 7.22
Solved Problems 7.22
Multiple Choice Questions 7.25
Answers 7.29
Review Questions 7.29
Chapter 8 Semiconductors 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 8.10
8.4 Extrinsic semiconductors 8.14
8.5 Carrier concentration in extrinsic semiconductors 8.17
8.6 Minority carrier life time 8.19
8.7 Drift and diff usion currents 8.22
8.8 Einstein’s relations 8.24
8.9 Continuity equation 8.25
8.10 Hall eff ect 8.29
8.11 Direct and indirect band gap semiconductors 8.31
8.12 Formation of p-n junction 8.33
8.13 Energy band diagram of p-n diode 8.36
8.14 Diode equation 8.37
8.15 p-n junction biasing 8.37
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