The Physics Around You

612 Pages·1988·56.17 MB·English

by  Dale D. Long

THE
PHYSICS
AROUND
YOU
LONG
SECOND EDITION
UCSUTSUEDDENBTOOSKTORESI

THE PHYSICS
AROUND YOU
Dale D. Long
Virginia Polytechnic Institute
and State University
Wadsworth Publishing Company
Belmont, California
A Division ofWadsworth, Inc.
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BRIEF
CONTENTS
1 Physics and You 1
PartOne MECHANICS 9
2 Forces and Motion 10
3 Gravitation and Motion along a Curve 32
4 Work and Energy 50
5 Momentum 83
6 Rotational Effects 98
7 Fluids 117
PartTwo HEAT 145
8 Heat Energy 146
9 ChangeofState 168
10 Transferof Heat 187
11 Using and Pumping Heat 211
Part Three WAVES AND SOUND 227
12 Waves 228
13 Sound 245
Part Four ELECTRICITYAND MAGNETISM 271
14 Electric Charge 272
15 Electric Current 291
16 Everyday Applicationsof Electricity 316
17 Electromagnetism 343
18 Electromagnetic Forces 356
19 Changing Magnetic Fields 369
20 Electrical Energy 382
Part Five LIGHTWAVES 401
21 Light Rays and Optical Devices 402
22 Light asa Wave 430
Part Six THE ATOM 447
23 Light as Particles 448
24 The Atom: A Closer Look 472
25 The Nucleus ofthe Atom 492
26 Nuclear Reactions and Nuclear Energy 518
27 The Theoryof Relativity 536
Appendix I Review ofAlgebra 561
Appendix II Handling Numbers 565
Appendix III Units and Conversion Factors 568
Appendix IV Suggestionsfor Solving Problems 573
Index 577
BriefContents
DETAILED
CONTENTS
To the Instructor xiii
Tothe Student xvii
1 Physics and You 1
1.1 What Is Physics? 2
1.2 Conservation Laws 4
1.3 Mathematics in This Book 5
Part One MECHANICS 9
2 Forcesand Motion 10
2.1 The Law ofInertia: Newton's First Law 11
2.2 The Description ofMotion 12
2.3 A Comment about Units 16
2.4 Changes in the State ofMotion: Newton's Second Law 17
2.5 Weight versus Mass 20
2.6 TheAction-Reaction Law: Newton's Third Law 22
2.7 Falling Bodies 24
2.8 OtherConstant Accelerations 27
3 Gravitation and Motion along a Curve 32
3.1 The Gravitational Force: One ofNature's Fundamental
Forces 33
Application: BlackHoles 36
1
3.2 Projectiles 38
3.3 Bodies in Circular Motion 40
4 Work and Energy 50
4.1 Work 51
4.2 Energy 54
4.3 KineticEnergy 54
4.4 Potential Energy 57
Application:Jefferson's "Seven-day" Clock 59
4.5 Energy Transformations 63
4.6 Conservation ofEnergy 64
4.7 Other Forms ofEnergy 69
4.8 Efficiency 70
4.9 Power 71
4.10 Energy and Society 73
5 Momentum 83
5.1 What Is Momentum? 83
5.2 Impulse 84
5.3 Conservation ofMomentum 87
5.4 Applications ofMomentum Conservation 90
6 Rotational Effects 98
6. Simple Machines 98
6.2 Torque 102
6.3 Applications to Complex Machines 107
6.4 Rotating Rigid Bodies 108
7 Fluids 117
7.1 Density and Specific Gravity 118
7.2 Pressure 120
7.3 Pressure Distribution in a Fluid 124
7.4 Bouyancy 126
7.5 Pumps 128
Application: TheHeart 130
—
7.6 Fluids in Motion Flying Airplanes and Curving
Baseballs 131
7.7 Molecular Forces and SurfaceTension in Liquids 134
DetailedContents