Walter F. Smith - Experimental Physics: Principles and Practice for the Laboratory

Experimental Physics

Principles and Practice for the Laboratory

Experimental Physics

Principles and Practice for the Laboratory

Edited by Walter Fox Smith

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Contents

Walter Fox Smith

Walter F. Smith

Walter F. Smith

Paul Thorman

Grace McKenzie-Smith

Walter F. Smith

Walter F. Smith

Brian Collett

Paul Freeman and Jami Shepherd

Walter F. Smith

Justin Peatross and Michael Ware

Walter F. Smith

Joseph Kozminski

Melissa Eblen-Zayas

Walter F. Smith

Mason Klein

Nathan C. Keim

Robbie Berg and Glenn Stark

Jay Sharping and Walter F. Smith

Enrique J. Galvez

Brett Fadem

The authors of this book deeply thank the following people, each of whom has put in many hours specifically for this book, testing experiments, organizing groups of student testers, providing insightful feedback, helping with editing, and creating figures. Without their help, this book would not have been possible: Eric Beery, Charles Bene, Ayesha Bhika, Travis Crawford, Jackson Davis, John Dusing, Sara Fadem, Michael Fernandez, Moira Ferrer, Helena Frisbie-Firsching, Rebeckah Fussell, Shamira Gonzalez, Lou Han, Charles Holbrow, Sunxiang Huang, Merritt Jacob, Meredith Jones, Lucas Kasle, Julia Kotler, Brian Kroger, Sasha Levine, Kate Matthews, Oliver Maupin, Aidan McGuckin, Marian McKenzie, Dani Medina, Saul Medrano, Alan Mendez, Richard Morash, Axel Moreen, Carly Press, Kristina Qualben, Margarita Rivers, Adeeb Saed, James Silva, Jonathan Simpson, Jeanette Smit, Greg Soos, Emily Swafford, Elizabeth Teng, Ryan Terrien, Kelly Tornetta, James Vickery, Jonam Walter, Longqi Wu, Shufan Xia, and Hongwen Yu.

We are also grateful to the many students in our classes over the last several years who have done the labs in this book, and because of their hard work and enthusiasm have given us critical feedback.

The development of the labs in was funded by grants to Prof. Enrique Galvez from the divisions of Undergraduate Education and Physics of the National Science Foundation.

You are holding the most important textbook ever written. Im being humorous, of course, but only partly. Science is the most important field. Physics is the most important science; in addition to the amazing, world changing discoveries made in physics itself, physics underlies all the other sciences and fields of engineering, and is responsible directly or indirectly for the biggest advances in them. Physics is based on experimental results, so the most important physics book is about experimental physics. This is by far the best experimental physics book ever written. (For example, its the only one written by a team of experts in each subfield of experimental physics, each of us having a deep devotion to undergraduate education.)

If youre using this book as part of a course, buckle up! You will find yourself challenged in ways youve never been before. You may find that the course is harder or less hard than other advanced physics courses youve taken, but it will definitely be very different. Youll be asked to master techniques that are used in cutting-edge research labs, to think very deeply about what youre doing, and (as you progress through the course) to become more independent as an experimental physicist, to design your own experiments, troubleshoot them yourself, and develop your own models to explain what you see.

Your approach to this course must be different from what youve done before . You truly have to do the pre-lab reading before lab, and far enough before that you can ask your instructor or classmates about anything that is unclear before lab. Otherwise, you will find yourself totally lost in lab, understanding only a small fraction of what youre supposed to, using more of the instructors time than is your fair share, and having to stay later than the other students.

If you put in the effort needed to prepare properly, you will find much delight in the labs. Youll also find plenty of frustration thats part of experimental physics. But solving the problems and puzzles that arise will be deeply satisfying.

Perhaps you will come up with a question that you and your instructor think many other students would have. Please email it to me, Walter F. Smith, wsmith@haverford.edu. I will add it to the FAQ on the books website, with credit to you and your instructor. (You can ask not to be credited if you prefer.) Also, please email me with any other suggestions for the book.

For each chapter, please look at the resources on the books website, ExpPhys.com . There, you will find important updates, additional instructional materials, links to related research, and occasional amusing anecdotes and other content.

Happy experimenting!

Advanced lab courses have two central goals that are in tension with each other. One is concrete: to teach students about the most important experimental and data analysis techniques. This is most efficiently accomplished with a series of well-defined, programmed exercises. However, there is also an essential and more abstract goal: to transform students, at least partly, into independent experimentalists. Students should learn how to formulate worthwhile research questions, and how to discover what is already known about the area of research. They should begin to understand the strengths and weaknesses of the range of experimental techniques that might be applied. They should become more confident in their ability to design, assemble, and debug experimental apparatus, to use it to take meaningful data, and to analyze the data in a way that most clearly shows its meaning.