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Physics is what it’s all about. What what’s all about? Everything. Physics is present in every action around you. And because physics is everywhere, it gets into some tricky places, which means it can be hard to follow. Studying physics can be even worse when you’re reading some dense textbook that’s hard to follow.

For most people who come into contact with physics, textbooks that land with 1,200-page whumps on desks are their only exposure to this amazingly rich and rewarding field. And what follows are weary struggles as the readers try to scale the awesome bulwarks of the massive tomes. Has no brave soul ever wanted to write a book on physics from the reader’s point of view? Yes, and here we come with such a book.

About This Book

This book is different. Instead of writing it from the physicist’s or professor’s point of view, we wrote it from the reader’s point of view. After thousands of one-on-one tutoring sessions, we know where the usual book presentation of this stuff starts to confuse people, and we’ve taken great care to jettison the top-down kinds of explanations. You don’t survive one-on-one tutoring sessions for long unless you get to know what really makes sense to people – what they want to see from their points of view. In other words, we designed this book to be crammed full of the good stuff – and only the good stuff. You also discover unique ways of looking at problems that professors and teachers use to make figuring out the problems simple.

This book is crammed with physics examples and physics problems. It’s designed to show you how to tackle the kinds of problems you may encounter in physics classes.

In this book, you can find solutions to problems similar to the ones you’re asked to solve elsewhere. And when you see how it’s done, solving similar problems should be a breeze.

From time to time, we include sidebars to provide a little more insight into what’s going on with a particular topic. They give you a little more of the story, such as how some famous physicist did what he did or an unexpected real-life application of the point under discussion. You can skip these sidebars, if you like, without missing any essential physics.

Some books have a dozen conventions that you need to know before you can start. Not this one. All you need to know is that variables and new terms appear in italics, like this, and that vectors – items that have both a magnitude and a direction – appear in bold. Web addresses appear in monofont.

Foolish Assumptions

In writing this book, we made some assumptions about you:

✔ You have no or very little prior knowledge of physics.

✔ You have some math prowess. In particular, you know algebra and a little trig. You don’t need to be an algebra pro, but you should know how to move items from one side of an equation to another and how to solve for values.

✔ You want physics concepts explained clearly and concisely, and you want examples that let you see those concepts in action.

✔ You want to work through some physics problems on your own. You’ll find plenty of practice problems in this book along with step-by-step solutions in case you get stuck.

Beyond the Book

In addition to the material in the print or e-book you’re reading right now, this product also comes with some access-anywhere goodies on the web. Check out these features:

✔ Cheat Sheet (www.dummies.com/cheatsheet/ucanphysics1): When you need a quick refresher, refer to the Cheat Sheet for some handy equations and the values of important constants.

✔ Dummies.com articles (www.dummies.com/extras/ucanphysics1): Each part in this book is supplemented by a relevant online article that provides additional tips and techniques related to the subject of that part. Read helpful articles that reveal how to draw a free-body diagram, how to use energy diagrams, the Carnot cycle, and ten physics heroes.

✔ Online practice and study aids: The online practice that comes free with this book offers 500 questions and answers that allow you to gain more practice with physics concepts. The beauty of the online questions is that you can customize your online practice to focus on the topics that give you the most trouble. So if you need help with projectile motion or angular momentum, just select those question types online and start practicing. Or if you’re short on time but want to get a mixed bag of a limited number of questions, you can specify the number of questions you want to practice. Whether you practice a few hundred questions in one sitting or a couple dozen, and whether you focus on a few types of questions or practice every type, the online program keeps track of the questions you get right and wrong so you can monitor your progress and spend time studying exactly what you need.

To gain access to the online practice, all you have to do is register. Just follow these simple steps:

1. Find your access code.

● Print-book users: If you purchased a hard copy of this book, turn to the inside of the front cover to find your access code.

● E-book users: If you purchased this book as an e-book, you can get your access code by registering your e-book at www.dummies.com/go/getaccess. Simply select your book from the drop-down menu, fill in your personal information, and then answer the security question to verify your purchase. You’ll then receive an email with your access code.

2. Go to http://studyandprep.wiley.com.

3. Click on the product you want to access, and then click Login.

4. On the Register tab, enter your access code, and click Go.

5. Follow the instructions to create an account and set up your personal login.

Now you’re ready to go! You can come back to the online program as often as you want – simply log on with the username and password you created during your initial login. No need to enter the access code a second time.

Tip: If you have trouble with your access code or can’t find it, contact Wiley Product Technical Support at 877-762-2974 or go to http://wiley.custhelp.com.

Where to Go from Here

You can leaf through this book; you don’t have to read it from beginning to end. Like other For Dummies books, this one was designed to let you skip around as you like. This is your book, and physics is your oyster. You can jump into Chapter 1, which is where all the action starts; you can head to Chapter 2 for a discussion of the necessary algebra and trig you should know; or you can jump in anywhere you like if you know exactly what topic you want to study.