# Mechanics and Relativity

Timon Idema

Copyright Year: 2018

Publisher: TU Delft Open

Language: English

## Formats Available

## Conditions of Use

Attribution-NonCommercial-ShareAlike

CC BY-NC-SA

## Reviews

The author presents Classical Mechanics in the first 9 chapters and Special Relativity Theory in the last 6 chapters. The section on Classical Mechanics is quite comprehensive; it touches on all the introductory topics that are generally... read more

The author presents Classical Mechanics in the first 9 chapters and Special Relativity Theory in the last 6 chapters. The section on Classical Mechanics is quite comprehensive; it touches on all the introductory topics that are generally presented in that type of course. The section on Relativity is somewhat less comprehensive. It does cover many of the topics in a beginning course, such as kinematics and dynamics; it seems, though, to be weak in its coverage of relativistic effects involving electromagnetism. The Index appears to be complete and to refer to the topics with, in many cases, multiple page references.

The content appears to have no errors and to be consistent with all other physics books of its level. The author makes a completely objective and unbiased presentation and doesn’t attach any aspect of his views or opinions to any of the topics.

In many cases, the word “accuracy” implies that the numerical values found in a derivation, a problem, or an example should match the reality. In perusing the text, one finds the author’s use of numerical results to be essentially zero. The author presents his arguments and their solutions purely in symbolic form. In the introduction, he stresses that numbers should be applied only at the end of a problem; up to that point, an analysis should be carried out symbolically; this, he indicates, leads to a deeper understanding of the problem at hand. This represents an interesting and valuable insight into a pedagogy that can be successful in the training of physicists.

The word “relevance” doesn’t mean too much without a reference to what something is relevant to. We’ll assume here that the matter at hand to which the textbook is relevant is the world at large. This is a textbook about Physics, and, particularly, about the Laws of Motion and of Forces. Everything the author speaks of is completely relevant to our understanding and our application of these Laws, which govern all motions in all times and places. The subject matter is no different from what has been taught for the last three centuries, in the case of mechanics, and for the last century, in the case of Relativity.

Here, the author assumes that the reader has a sufficient background in mathematics to be able to follow along step-by-step; the author doesn’t show precisely how one equation leads on to the next; he assumes that the reader can make those small jumps of reasoning. For such readers, the level of clarity is quite high; if the reader lacks that background, the level of clarity will be quite low. In each section, the author proceeds step-by-step in laying out the reasoning for each topic. The equations, which are the gist of his arguments, move from one to the other with intervening paragraphs that add information and that direct the reader on to the next step. Figures are provided to enhance the understanding. Overall, the textbook is quite well-done in regard to clarity. Regarding the writing style, the author appears to have taken care to write in a manner that can be accessible to most any student with the proper mathematical background.

One idea leads on inexorably to the next. The presentation of the topics here is logical and sequential, with new topics being defined and integrated with prior presentations. This is to be expected in all good Physics books. In this regard, the textbook is highly consistent, as all Physics books must be.

The author says in the Preface,

“In the first part on classical mechanics, the chapters do not necessarily be taught or read in the order I have presented them. Many of the concepts of chapter 8 can be understood based on the material covered in chapters 1-3. In the second part we discuss the special theory of relativity, for which especially chapters 3 on energy and 4 on momentum from the first part are important. There are thus multiple paths you can take, and I encourage you to look ahead sometimes to see how what is yet to come ties in with what is discussed at a given point in the book.”

The idea of modularity is quite consistent with this statement. There being “multiple paths you can take” means that the text can be creatively reordered, maintaining, though, the logical sequence of the material, in order to accomplish the goals of any given course.

As commented above under the headings, Comprehensiveness and Consistency, the subject matter requires an orderly presentation, which is the norm for subjects like this. The author has provided a well-organized text here, with the material on one chapter in each of the two major divisions providing the basis for the continuation into the next section; similarly, the Relativity portion of the text is well-grounded in the material of the Mechanics portion. Related to this idea are the Appendices which contain material the student might find useful (though not the solutions to the end-of-chapter problems). The index is well organized and spans 2.2 pages; it appears to be fairly complete.

The Table of Contents and the Index are well-ordered permitting the reader to navigate freely and accurately through it. The Figures are well-placed with respect to their referential text; the captions are complete and relate the Figure’s story as a good supplement to the text.

I’ve seen no instance of poor grammar, incorrect spelling, or sentence structure in my inspection of the text.

I believe this category is irrelevant here. The Laws of Motion apply evenly to all worlds at all times. For example, we cannot correctly say that Newton’s Laws apply more to Europe than they do to Asia, or more to us today than they did to the Aztec Empire in its heyday.

In his Preface, the author pointed out that inserting numbers in the calculations used in derivations and problems detracted from the learning the students and the readers are after. By just using symbols throughout, until it is necessary to acquire a numerical answer, the readers' attention is kept on the operation of the Laws and the relationships therein are kept in full view. This strikes me as a good pedagogy that is often given short shrift.

## Table of Contents

- Chapter 1: Introduction to classical mechanics
- Chapter 2: Forces
- Chapter 3: Energy
- Chapter 4: Momentum
- Chapter 5: Rotational motion, torque and angular momentum
- Chapter 6: General planar motion
- Chapter 7: General rotational motion
- Chapter 8: Oscillations
- Chapter 9: Waves
- Chapter 10: Einstein's postulates
- Chapter 11: Lorentz transformations
- Chapter 12: Spacetime diagrams
- Chapter 13: Position, energy and momentum in special relativity
- Chapter 14: Relativistic collisions
- Chapter 15: Relativistic forces and waves

## Ancillary Material

## About the Book

In Mechanics and Relativity, the reader is taken on a tour through time and space. Starting from the basic axioms formulated by Newton and Einstein, the theory of motion at both the everyday and the highly relativistic level is developed without the need of prior knowledge. The relevant mathematics is provided in an appendix. The text contains various worked examples and a large number of original problems to help the reader develop an intuition for the physics. Applications covered in the book span a wide range of physical phenomena, including rocket motion, spinning tennis rackets and high-energy particle collisions.

## About the Contributors

### Author

**Dr. T. (Timon) Idema** is an associate professor at the Department of Bionanoscience at Delft University of Technology (TU Delft) in The Netherlands. Before starting his research group in Delft in 2012, Idema obtained his PhD in theoretical biophysics at Leiden University (The Netherlands) and worked at the Institut Curie (Paris, France) and the University of Pennsylvania (Philadelphia, USA). Idema’s group studies collective dynamics in biologically motivated systems, ranging from proteins at the nano scale to tissues and even populations at the micro- and macro scale. A theorist himself, Idema frequently collaborates and co-publishes with experimental groups. He also teaches a number of courses at TU Delft, ranging from introductory physics to courses on soft matter and geometry that take students to the cutting edge of current research. For more details on his group’s research and teaching activities, visit their website at idemalab.tudelft.nl.