I had high hopes for this book because it is always fun to find out how things work. Unfortunately, the book did not live up to my hopes. I could tell just a few pages in that Kakalios assumes his readers have a basic knowledge of physics, such as having taken a high school class. He assumes readers know terms like mass, amplitude, digital, magnetic polarities, magnetic induction and infrared radiation because he uses them early on without defining them. He assumes readers know about voltage and why 110 is higher than 120.
He writes early on about moving electric charges generating a magnetic field but does not explain why or how. (4) I wish he would have explained early and well the relationship of electric and magnetic fields and how one affects the other and used lots of diagrams. That would have made the explanation of an electric tooth brush recharger much easier to understand, for example. (He finally has a diagram later, on page 43.)
When explaining the principles of a refrigerator, he assume readers know how a gas being compressed to a liquid gives up heat. He writes about molecules with kinetic energy and that may be confusing to readers. Kakalios had earlier explained kinetic energy using a pendulum but never transferred the concept to molecules and how some have more kinetic energy than others.
Sometimes I found his writing just confusing. When writing about a pendulum, he writes of increasing the potential energy of the bob by “lifting it up.” (2) I pictured lifting the bob up vertically. What he really meant was to grasp the bob and swing it to the side in an arc, making sure the string remained taut.
Here's another example of his writing when discussing a thermometer and the thermal expansion of a liquid when heated. “This leads to a small but real net relative displacement of the atom with rising temperature.” (68) He could have written, “That means the space the atom occupies increases as the temperature rises.”
That being said, there are aspects of this book I like. Kakalois explains many interesting phenomena, such as CAT scans and MRIs, airport scanners, noise canceling earphones, touch screens and many more. I learned much, like what kind of radiation is harmful and what kind is non-ionizing. I learned that the radio signals from the chip in my credit card has a short range of about four feet so others cannot eavesdrop on my transaction. I found out the code for my remote entry fob changes every time I use it, as does the coordinated receiver.
Some of his explanations were great, such as the movie theater illustration representing semiconductors. It was clearly understandable. I wish there had been many more illustrations in the book as many of Kakalois' explanations would have been much easier to understand with them.
If you have a high school background in physics and understand many physics terms, you will appreciate this book and benefit from what is in it. If you do not have a familiarity scientific terms, you may have difficulty understanding this book.
My rating: 3/5 stars.
James Kakalios is the Taylor Distinguished Professor of Physics at the University of Minnesota and the author of the bestselling The Physics of Superheroes.
Crown, 256 pages.
I received a complimentary copy of this book from the publisher. My comments are an independent and honest review.