This is a story about how Rereko, a fairly ordinary high school student from the advanced world of Electopia, gets sent to Earth for remedial courses in the science of electricity. Her society expects absolutely everyone to know a little something about how electricity behaves, and its more important applications. Since she’s a little bit slow in this subject, a tutour from our own, more primitive planet, may be just her speed. A Tokyo graduate student in electrical engineering, Hikaru, seems like the perfect fit.

Like the other books in this series, The Manga Guide to Electricity aims to break down potentially difficult subject matter into bite-sized, comic book chunks, all wrapped up in an engaging story. While the target audience is individuals interested in the subject matter rather than manga fans only after a fun read, the story provides a natural vehicle for the book to give lots of real-life examples of the subject in question, an endless litany of answers to the unasked question: why does this stuff matter, anyway? As usual, the book features a tutour and a (sometimes reluctant) student.

The dialogue-based format is not only an effective way of unpacking concepts, but also makes it easy to build up a book-length political argument simultaneously: that this information is important and worthwhile even for an average citizen. Plato made Socratic dialogue famous in his philosophical treatises, Galileo appropriated it for the use of scientific education, and Ohmsha and No Starch Press did both of them one better by adding pretty pictures. You almost can’t go wrong.

The focus of this book is on applications. It’s at least as much about basic electrical engineering as it is about electrostatics and electrodynamics. The abstract concepts of electric forces and fields are not really touched on. Point charges don’t come into it. Instead, we jump directly into circuits, explicitly using the analogy of electricity as flowing water: voltage is pressure; current is rate of flow. This is a very useful picture, although there are times it could have been used to greater effect.

The only weakness in this book, from my perspective, is failing to take a little more time to fully flesh out some of the basics. Voltage, current, and resistance are all explained very well. The reader is not simply given a definition, but aided in visualizing the real physical meaning of the concepts. However, the relationship between them is not as well explained. The current is equal to the voltage over the resistance. Why does a higher voltage result in a higher currrent? It’s analogous to increasing the water pressure, forcing it through even faster. Why does an increased resistance lower the current? It’s analogous to constraining or restricting the path, slowing each individual drop of water down.

This and a few other concepts were not sufficiently spelled out, though the formula was introduced. On the other hand, a tremendous number of applications were discussed, although many of them were only roughly sketched out: transformers, generators, semiconductors, diodes, and transistors of many kinds. These thumbnail sketches were appropriately short, and a writer with less of an engineering background may even have left some of them out, but a writer with a pure physics background probably would have spent a little more time on some of the basic concepts, and this is my own background, so I admit my bias.

Still, a solid overview of the topic. I really like the practical, real-life examples that are a hallmark of this series. The very first chapter started by looking at the labels on kitchen appliances, and this was a brilliant way of introducing the topic. And I was quite surprised, I didn’t expect to learn something new in this book, but actually a good chunk of the material was unfamiliar territory for me. I didn’t know that much about the basic physical operations of diodes, transistors, or some of the other types of electrical technologies discussed. It makes me want to learn more about electrical engineering. After all, who isn’t crazy about all the electronic gadgets that make our modern world go round?

(No Starch Press, 2009)

Reprinted with permission from The Sleeping Hedgehog
Copyright (2011) The Sleeping Hedgehog