Statics For Dummies E-Book

James H. Allen

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 481

Veröffentlichungsjahr: 2010

Beschreibung

The fast and easy way to ace your statics course

Does the study of statics stress you out? Does just the thought of mechanics make you rigid? Thanks to this book, you can find balance in the study of this often-intimidating subject and ace even the most challenging university-level courses.

Statics For Dummies gives you easy-to-follow, plain-English explanations for everything you need to grasp the study of statics. You'll get a thorough introduction to this foundational branch of engineering and easy-to-follow coverage of solving problems involving forces on bodies at rest; vector algebra; force systems; equivalent force systems; distributed forces; internal forces; principles of equilibrium; applications to trusses, frames, and beams; and friction.

• Offers a comprehensible introduction to statics
• Covers all the major topics you'll encounter in university-level courses
• Plain-English guidance help you grasp even the most confusing concepts

If you're currently enrolled in a statics course and looking for a friendlier way to get a handle on the subject, Statics For Dummies has you covered.

Leseprobe

Statics For Dummies®

Table of Contents

Introduction

About This Book

Conventions Used in This Book

What You’re Not to Read

Foolish Assumptions

How This Book Is Organized

Part I: Setting the Stage for Statics

Part II: Your Statics Foundation: Vector Basics

Part III: Forces and Moments as Vectors

Part IV: A Picture Is Worth a Thousand Words (Or At Least a Few Equations): Free-Body Diagrams

Part V: A Question of Balance: Equilibrium

Part VI: Statics in Action

Part VII: The Part of Tens

Icons Used in This Book

Where to Go from Here

Part I: Setting the Stage for Statics

Chapter 1: Using Statics to Describe the World around You

What Mechanics Is All About

Putting Vectors to Work

Peeking at a few vector types

Understanding some purposes of vectors

Defining Actions in Statics

Sketching the World around You: Free-Body Diagrams

Unveiling the Concept of Equilibrium

Applying Statics to the Real World

Chapter 2: A Quick Mathematics Refresher

Keeping Things Accurate and Determining What’s Significant

Nomenclature with Little Superscripts: Using Scientific and Exponential Notation

Recalling Some Basic Algebra

Hitting the slopes of functions and lines

Rearranging equations to solve for unknown variables

Sigma notation

Getting into Shapes with Basic Geometry and Trigonometry

Getting a handle on important geometry concepts

Tackling the three basic identities of trigonometry

Brushing Up on Basic Calculus

The power rule: Differentiation and integration of polynomials

Using calculus to define local maximum and minimum values

Chapter 3: Working with Unit Systems and Constants

Measuring Up in Statics

The metric system

U.S. customary units

The kip: One crazy exception

Never the twain shall meet: Avoiding mixing unit systems

Looking at Units of Measure and Constants Used in Statics

Constants worth noting

Three common statics units for everyday life

All the derived units you’ll ever need

Part II: Your Statics Foundation:Vector Basics

Chapter 4: Viewing the World through Vectors

Defining a Vector

Understanding the difference between scalars and vectors

Taking a closer look at vectors

Applying vector basics

Drawing a Vector’s Portrait

The single-headed arrow approach

A two-headed monster: The double-headed arrow approach

Exploring Different Types of Vectors

Fixed vector

Free vector

Sliding vector

Chapter 5: Using Vectors to Better Define Direction

Taking Direction from the Cartesian Coordinate System

As a Crow Flies: Using Position Vectors to Determine Direction

Describing direction in detail

Moving from Point A to Point B and back again

A First Glance at Determining a Vector’s Magnitude

Recognizing the notation for magnitude

Computing the magnitude of a position vector: Pythagoras to the rescue!

Unit Vectors Tell Direction, Too!

Cartesian-vector notation

Using unit vectors to create position vectors

Creating Unit Vectors from Scratch

Shrinking down position vectors

Using angular data and direction cosines

Utilizing proportions and similar triangles

Knowing which technique to use

Chapter 6: Vector Mathematics and Identities

Performing Basic Vector Operations

Adding vectors

Subtracting vectors

Moving vectors head to tail

What Do You Mean I Can’t Multiply Vectors? Creating Products

Dot products

Cross products

Useful Vector Operation Identities

Chapter 7: Turning Multiple Vectors into a Single Vector Resultant

Getting a Handle on Resultant Vectors

Depicting a resultant vector

Principles of resultants

Calculating resultant magnitude and direction

Using Graphical Techniques to Construct Resultants

Using Geometric Methods to Construct Resultants: The Parallelogram Method

Useful geometric relationships

The parallelogram method

Using Vector Methods to Compute Resultants

Using vector addition

Calculating the direction of the vector resultant

Chapter 8: Breaking Down a Vector into Components

Defining a Vector Component

Resolving a Vector into Cartesian and Non-Cartesian Components

Using Cartesian concepts to calculate Cartesian components

Determining components on a non-Cartesian orientation

Calculating non-Cartesian components of two-dimensional vectors

Part III: Forces and Moments as Vectors

Chapter 9: Applying Concentrated Forces and External Point Loads

Comparing Internal and External Forces and Rigid and Deformable Bodies

Exploring External Concentrated Forces

Normal forces from contact

Friction

Concentrated loads

Revealing the Unseen with Concentrated Internal Loads

Forces in ropes and cables

Forces in springs

Surveying Self Weight as an External Load Value

Getting specific on specific gravity and self weight properties

Working with lumped mass calculations

Introducing the Principle of Transmissibility

Chapter 10: Spreading It Out: Understanding Distributed Loads

Getting a Handle on Some Distributed Load Vocab

Take a (Distributed) Load Off: Types of Distributed Loads

Distributed forces

Surface loads (pressures)

Volumetric loads

Calculating the Resultant of a Distributed Load

Uniform and linearly varying forces

Surface loads and pressures in multiple dimensions

Avoiding the double integral

Looking at Mass and Self Weight as Distributed Values

Chapter 11: Finding the Centers of Objects and Regions

Defining Location for Distributed Loads

Getting to the Center of Centroids

Defining a centroid’s region type

Computing the centroid of a discrete region

Finding centroids of continuous regions

Taking advantage of symmetry

Understanding Centers of Mass and Gravity

Center of mass

Center of gravity

Chapter 12: Special Occasions in the Life of a Force Vector: Moments and Couples

I Need a Moment: Exploring Rotation and Moments of Force

Developing rotational behaviors: Meeting couples and concentrated moments

Taking on torque and bending: Types of concentrated moments

Getting a handle on the right-hand rule for moments of force

Calculating a Moment with Scalar Data

Planar rotation about a point

Determining the magnitude and sense of a two-dimensional couple

Calculating a Moment by Using Vector Information

Completing the cross product

Using unit vectors to create moment vectors

Using Double-Headed Arrows to Find Moment Resultants and Components

Relocating a Force by Using a Moment: Equivalent Force Couples

Part IV: A Picture Is Worth a Thousand Words (Or At Least a Few Equations):Free-Body Diagrams

Chapter 13: Anatomy of a Free-Body Diagram

Free-Body Diagrams in a Nutshell

Displaying External Forces

Portraying concentrated forces

Depicting distributed forces

Looking at the F.B.D. so far

Conveying concentrated moments

Axial Loads and Beyond: Depicting Internal Forces

Restricting Movements with Support Reactions

Three basic planar support reactions

Three-dimensional support conditions

Weighing In with Self Weight

Chapter 14: The F.B.D.: Knowing What to Draw and How to Draw It

Getting Your F.B.D. Started

Assuming a direction for support reactions

Including more than the required info on your F.B.D.

Zooming In with Isolation Boxes

Unveiling internal forces

Applying rules of application

Avoiding problems with incorrect isolation techniques

Using Multiple F.B.D.s

Chapter 15: Simplifying a Free-Body Diagram

Presenting the Principle of Superposition

Centering on Centerlines and Lines of Symmetry

Equivalent Systems: Forces on the Move

Moving a force: The space potato analogy

Moving a moment

Part V: A Question of Balance: Equilibrium

Chapter 16: Mr. Newton Has Entered the Building: The Basics of Equilibrium

Defining Equilibrium for Statics

Translational equilibrium

Rotational equilibrium

Looking for Equilibrium with Newton’s Laws

Reviewing Newton’s laws of motion

The scalar equations that make it happen: The big three

Identifying Improper Constraints: When Equilibrium Equations Are Insufficient

Concurrent force systems

Parallel force systems

Chapter 17: Taking a Closer Look at Two-Dimensional Equilibrium:Scalar Methods

Tackling Two-Dimensional Statics Problems in Three Basic Steps

Calculating Support Reactions with Two-Dimensional Equilibrium Equations

First things first: Creating the F.B.D.

Writing the equilibrium equations

Choosing a Better Place to Sum Moments

Chapter 18: Getting Better Acquainted with Three-Dimensional Equilibrium: Vector Methods

Finding a Starting Point

Seeing Equilibrium within Vector Notation

Equilibrium in translational behaviors

Rotational components

Figuring Support Reactions with Three-Dimensional Equilibrium Equations

Establishing the F.B.D.

Writing the equilibrium equations

Part VI: Statics in Action

Chapter 19: Working with Trusses

Identifying Truss Members

The Method of Joints: Zooming In on One Panel Point at a Time

Step 1: Drawing isolation boxes

Step 2: Applying the equations of equilibrium

Step 3: Review and repeat

Drawbacks to the Method of Joints

And Now for My Next Trick: Slicing through the Method of Sections

Step 1: Cutting the truss

Step 2: Drawing the F.B.D. for the two remaining truss pieces

Step 3: Applying the equations of translational equilibrium

Step 4: Applying the equation of rotational equilibrium

Step 4, continued: Identifying the instantaneous center

Shortcutting the Equation Writing: Zero-Force Members

Chapter 20: Analyzing Beams and Bending Members

Defining the Internal Bending Forces

And then there were three: Internal forces of two-dimensional objects

Strange new three-dimensional effects

Calculating Internal Loads at a Point

Positive moments make you happy!: Yet another two-dimensional sign convention

Using the sign convention

Computing internal force magnitudes

Writing Generalized Equations for Internal Forces

Defining the critical points

Establishing the regions of your generalized equations

Discovering other useful tricks from generalized equations

Creating Shear and Moment Diagrams by Area Calculations

Rules to remember when working with area methods

Constructing the shear diagram

Creating the moment diagram

Chapter 21: Working with Frames and Machines

Identifying a Frame and Machine System

Defining properties of frames and machines

Determining static determinacy

Using the Blow-It-All-Apart Approach to Solve Frame and Machine Problems

Breaking it at the hinges

Knowing where to start solving frame and machine problems

Considering Other Useful Approaches to Common Frame and Machine Problems

When more than two members meet at an internal hinge

Dealing with pesky pulley problems

Tackling Complex and Unique Assemblies on Machine Problems

Pistons and slider assemblies

Slotted holes and unidirectional pins

Chapter 22: A Different Kind of Axial System: Cable Systems

Defining Nonlinear Structural Behavior

Distinguishing among Types of Flexible Cable Systems

Recognizing cables under concentrated loads

Picking out parabolic cable systems

Identifying catenary cable systems

Solving for Tension in Flexible Cables

Concentrated load systems

Parabolic cable systems

Catenary cable systems

Taking a Shortcut: The Beam Analogy for Flexible Cables

Chapter 23: Those Darn Dam Problems: Submerged Surfaces

Feeling the Pressure: Understanding Fluid Pressure

Dealing with hydrostatic pressure

Determining effects from the self weight of water

Making Calculations under (Fluid) Pressure

Drawing the fluid F.B.D.

Creating the hydrostatic pressure distribution

Finding the dead weight of water and dams

Including base reactions for dam structures

Applying equilibrium equations

Figuring Partial Pressures on Openings and Gates

Chapter 24: Incorporating Friction into Your Applications

Friction: It’s More Than Just Heat!

Factors affecting friction

Types of friction

A Sense of Impending . . . Motion? Calculating Sense

Establishing equilibrium when friction is present

Finding the friction limit F-MAX

Solving Friction Problems by Using Logic and Equations Together

Working with friction angles

Combining friction and normal forces into a single resultant

Timber! Exploring Tipping

Uncovering the tipping point and normal force

Moving the normal force to prevent tipping

Establishing which friction phenomenon controls, sliding or tipping

Examining More Common Friction Applications

Wedging in on the action

Staying flexible with belts and pulleys

Part VII: The Part of Tens

Chapter 25: Ten Steps to Solving Any Statics Problem

Sketches Come First

Determine the Supports

Don’t Forget the Applied Loads and Self Weight

Calculate As Many Unknown Support Reactions As You Can

Guess It’s a Frame or Machine

Get Out the Dynamite: Separating Pieces from the Problem for Internal Analysis

Assume Directions of Internal Forces

Be Consistent with Your Assumptions

Guess That Three (or Six) Equilibrium Equations Are Necessary

If Friction Is Involved, Guess That the Object Slides

Chapter 26: Ten Tips for Surviving a Statics Exam

Find Problems You Know How to Solve

State Your Assumptions

Relax and Remember Your Basic Steps

Identify Your Origin and Coordinate System

Remember Your Vectors

Write Your Equilibrium Equations

Stuck? Draw More Free-Body Diagrams

Draw Your Shear and Moment Diagrams Correctly

Assess Your Answers

Acknowledge Mistakes and Don’t Erase

Statics For Dummies®

by James H. Allen III, PE, PhD

Statics For Dummies®

Published byWiley Publishing, Inc.111 River St.Hoboken, NJ 07030-5774www.wiley.com

Copyright © 2010 by Wiley Publishing, Inc., Indianapolis, Indiana

Published by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

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About the Author

James H. Allen III, PE, PhD, serves on the civil engineering faculty at the University of Evansville, where he teaches statics, structural analysis, and structural design courses. Dr. Allen received his PhD from the University of Cincinnati in structural engineering and performed his undergraduate work at the University of Missouri-Rolla (now the Missouri University of Science and Technology).

Dedication

To my wife Miranda for her unconditional love and support.

Author’s Acknowledgments

I wish to thank all of the many people that have worked so hard to make this book a reality. Thanks especially to my senior project editor, Alissa Schwipps, for her patience and guidance, and to all of the others who have made this project possible, including Mike Baker, Megan Knoll, and Wiley’s Composition Services department. Thanks for all you do!

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Introduction

As I watch students working toward mastering the principles of statics, I find myself frequently answering some of the same basic questions. Despite countless hours of working through examples and homework problems from their textbooks, students often seem to be confused on the same several topics.

The problem isn’t that the material in a typical statics class is overly difficult; I think the issue is just several simple misconceptions that manifest themselves through poorly written examples and unnecessarily complex wording in conventional statics textbooks.

That’s why I’ve written Statics For Dummies — to help students of the subject get a better understanding than they may otherwise get in a classic textbook. In this book, my goal is to answer those basic questions by using simple explanations and eliminating a lot of the extra technical jargon.

About This Book

No statics book can tell you how to solve every possible problem you encounter. What Statics For Dummies tells you is what you need to know and why you need to know it. Why are three-dimensional problems easier to solve with vector formulations than with scalar methods? What exactly is equilibrium, and how do Newton’s laws guarantee it? How do you know the difference between a truss and frame? All of these topics are at the heart of understanding statics; after you’ve got these basics down, actually solving a statics problem is a snap!

In statics, one of the most important habits to form is being as methodical as possible, which means that statics lends itself very nicely to a large number of checklists or simple steps to remember and follow. Throughout this book, I try to organize certain techniques by outlining the steps that you need to follow. Just like when you go grocery shopping, the checklists help you remember what fruits and vegetables (or equations or free-body diagrams) you need to put in your basket.

The best part of this book is that you have complete control on where you want to start. If you just want the tips for solving specific problems, jump to Part VI. If you find you need a bit of a refresher on vectors, that’s in Part II. Let the table of contents and index be your guides.

Conventions Used in This Book

I use the following conventions throughout the text to make things consistent and easy to understand:

New terms appear in italic and are closely followed by an easy-to-understand definition.

Bold is used to highlight the action parts of numbered steps, as well as keywords in bulleted lists.

I also use other, statics-specific conventions that I may not explain every time, so following is a brief list of concepts and terms that I use frequently throughout the book.

Decimal places: I try to carry at least three decimal places in all my calculations in this book. This move helps ensure enough precision in my calculations to demonstrate the fundamental principles without getting bogged down in the pesky numerical accuracy issues I cover in Chapter 2.

Vector variables: The most important aspect of statics is that you take all effects into consideration; if you forget even the smallest behavior on an object, solutions in statics can become impossible to accurately calculate. To help keep track, I usually use F or P to indicate force vectors, and M to indicate a moment vector. I also use i, j, and k to represent those common unit vectors in the text; in equations, they appear as .

Bold (not in steps): Aside from its use in numbered steps and bulleted lists, I also use bold text to represent a vector equation. If you see a bolded variable, that indicates a vector is lurking in the discussion. This convention is common to most classical textbooks, so I replicate it here just for the sake of consistency with vectors you may have already been exposed to in a conventional statics or physic class.

Arrows on top of vector names: Another method of denoting a vector is to use the label or name of the vector with an arrow over the top such as . If you see an arrow on top of a letter or word in an equation, you know that I’m working with vectors.

Italics (not as definitions): I also adopt a second sign convention from other textbooks: When I talk about a vector’s magnitude (length) in the text, I use the name or label of the vector in italics.

Absolute value brackets: To represent the magnitude of a vector in an equation, I surround it with absolute value brackets, such as . Because magnitudes are properties of vectors, I still include the vector arrow over the label. Just remember that the absolute value brackets take precedence, so if you see those, you know I’m primarily talking about a scalar magnitude.

Plus signs (+) with vector senses: Althoughit’s not required, I use the plus symbol before positive numbers in some vector calculations as a visual reminder that I have in fact considered the sense (direction) of the vector on the Cartesian plane.

Origin: I assume that the origin of any given Cartesian plane is (0,0) for two-dimensional problems and (0,0,0) for three-dimensional ones unless otherwise noted.

What You’re Not to Read

Although I hope you’re interested in every word I’ve painstakingly inscribed in this book, I admit that there are a few things you can skip over if you’re short on time or just after the most important and practical stuff.

Text in sidebars: Sidebars are the shaded boxes that provide extra information, such as history or trivia, about the chapter topic.

Anything with a Technical Stuff icon: The in-depth info tagged by this icon is useful, but it may not be entirely necessary to solve day-to-day problems. It may also include information that shows how the information being discussed was developed or how the formulations came about.

Foolish Assumptions

As I wrote this book, I made a few assumptions about you, my beloved reader.

You’re any college student taking an engineering statics class or studying Newtonian mechanics in your physics classes, or are at least familiar with those basic concepts.

You remember some math skills, including algebra and basic calculus topics such as differentiation and simple integration.

You have proficiency in geometry and trigonometry. The basic rules governing sines, cosines, and tangents of angles (both in degrees and radians) prove invaluable as you work a statics problem.

You’re willing to practice the techniques that I show you. Remember all those problems your math teachers made you work back in school? Statics may require a similar effort. Practice makes perfect!

How This Book Is Organized

This book starts with a basic review of units and math and goes through vectors, forces, free-body diagrams, equilibrium, and practical statics applications. Here’s the lowdown on each part.

Part I: Setting the Stage for Statics

In Part I, I give you some basic refresher information, such as working with units, while reviewing some of the basic math that provides the foundation for statics. Chapter 1 introduces the concept of statics while Chapter 2 provides you with a brief refresher about a wide range of mathematics topics, including basic algebra and polynomials, trigonometric relationships, and basic integration and differentiation of polynomials. Chapter 3 highlights the two major systems of units that you encounter in statics and shows you the base units for a wide range of values in statics.

Part II: Your Statics Foundation: Vector Basics

Part II introduces some basic vector principles. Chapter 4 shows you the three basic characteristics of vectors and how you can depict them graphically. Chapter 5 describes how to define your first vector, describing direction from one point to another. I also show you several alternative ways to define direction by using vectors. In Chapter 6, I explain the basics of vector mathematics and explore several useful identity relationships that come in handy. Chapter 7 demonstrates how to create one vector from multiple other vectors. I explain several basic techniques and show you how to apply basic formulas for calculations of each technique. Chapter 8 shows you the opposite information from Chapter 7: how you can split a single vector into multiple vectors acting in different directions.

Part III: Forces and Moments as Vectors

In Part III, I explore how load effects are created. In Chapter 9, I illustrate single concentrated loads (or point loads) and introduce you to the concept of self weight as a single value. Chapter 10 covers loads acting over an area or a distance and shows you how to turn a distributed load into an equivalent concentrated load as well. In Chapter 11, I show you how to calculate the different centroids (geometric centers, such as center of area and center of mass/gravity) of different geometric shapes, which proves useful for helping you to locate the single equivalent force of a distributed load. Chapter 12 is where I introduce rotational effects known as moments, explaining how to draw and calculate them.

Part IV: A Picture Is Worth a Thousand Words (Or At Least a Few Equations): Free-Body Diagrams

Part IV shows you how to draw the pictures necessary to solve statics problems. In Chapter 13, I give you the basic checklist of items to include on a free-body diagram (F.B.D.) and then explain how to define supports in terms of forces and moments. Chapter 14 shows you what to draw and how to work with multiple free-body diagrams at the same time. In Chapter 15, I give you some guidance on several ways to simplify some of the more complex diagrams that you create.

Part V: A Question of Balance: Equilibrium

In Part V, I introduce you to the concept of stability or equilibrium in statics. Chapter 16 defines the different types of equilibrium by explaining Newton’s three laws of motion and the basic assumptions behind the governing equations of statics. In Chapters 17 and 18, I show you how to apply the basic equations of equilibrium to solve for unknown support reactions in two- and three-dimensional problems, respectively.

Part VI: Statics in Action

In Part VI, I show you how to identify the major categories of problems you come across in the real world. I also highlight several tips and techniques to speed up your solution process. Chapter 19 introduces you to trusses and simple axial members. I show you the basic techniques for solving for internal forces in the members of the trusses. Chapter 20 shows you that for many members in statics, additional internal forces exist beyond just the simple axial cases. I show you how to write equations for these internal forces and how to draw a graph of their values. In Chapter 21, you discover how to deal with frames and machine structures. Chapter 22 provides you with tools necessary to solve for internal forces of systems whose internal forces vary with geometry; I explain the concepts of sag and tension and then provide a useful shortcut technique known as the beam analogy.

In Chapter 23, you sink to new depths by exploring the behavior of fluids on submerged surfaces. I explain the concept of pressure and unit width in your calculations, and how to apply the equations of equilibrium. Things really heat up in Chapter 24 as I introduce friction to the problems. I explain the logic needed to determine if an object is prone to tipping or sliding and how to mathematically prove that.

Part VII: The Part of Tens

Part VII includes helpful top-ten lists. Chapter 25 provides you with ten important statics ideas to remember even if you forget everything else, and Chapter 26 gives you ten tips to survive a statics exam.

Icons Used in This Book

To make this book easier to read and simpler to use, I include some icons that can help you find and identify key ideas and information.

This icon appears whenever an idea or item can save you time or simplify your statics experience.

Any time you see this icon, you know the information that follows points out a key idea or concept, greatly increasing the number of statics tools you have at your disposal.

This icon flags information that highlights dangers to your solution technique, or a common misstep that statics practitioners make but you should avoid.

This icon appears next to information that’s interesting but not essential. Don’t be afraid to skip these paragraphs.

Where to Go from Here

You can use Statics For Dummies either as a supplement to a course you’re currently taking or as a stand-alone volume for understanding the basic concepts of statics.

If you’re taking a statics course or studying Newtonian mechanics in physics, hopefully you find the organization to be very familiar. I follow the basic topics sequence that you experience in a class. However, unlike a classical text, if you want to skip a chapter, feel free.

If you’re studying on your own or have never had a statics class, I strongly urge you to start at the beginning with Chapter 1 and read the chapters in order. The techniques in the later chapters do build on concepts of early chapters. That being said, this book isn’t a mystery novel. If you want to skip ahead to the topics at the end, go right ahead; you won’t ruin the ending. And if you get really lost, you can always fall back to an earlier chapter for a quick refresher!

Part I

Setting the Stage for Statics

In this part . . .

This first part introduces you to the basic concepts of mechanics in engineering and the sciences, as well as the differences between the basic fields. You also pick up the basic assumptions you need when working statics problems. I explain the two primary systems of units (U.S. customary and metric) and introduce you to the base units of each system. Finally, I review basic algebra, geometry, trigonometry, and calculus, all of which you encounter frequently in statics.

Chapter 1

Using Statics to Describe the World around You

In This Chapter

Defining statics and related studies

Introducing vectors

Exploring free-body diagrams

Looking at specific applications of statics

Statics is a branch of physics that is especially useful in the fields of engineering and science. Although general physics may describe all the actions around you, from the waving of leaves on a tree to the reflection of light on a pond, the field of statics is much more specific.

In fact, statics is actually a part of most physics courses. So if you’ve ever taken a high school or college physics course, chances are that some of the information in this book may seem vaguely familiar. For example, one of the first areas you study in physics is often Newtonian mechanics, which is basically statics and dynamics.