How Things Work The Physics of Everyday Life


n today’s world we are surrounded by science and by 
the technology that has grown out of that science. For 
most of us, this is making the world increasingly mysterious and somewhat ominous as technology becomes 
ever more powerful. For instance, we are confronted by 
many global environmental questions such as the dangers of greenhouse gases and the best choices of energy 
sources. These are questions that are fundamentally technical in nature and there is a bewildering variety of claims 
and counterclaims as to what is “the truth” on these and 
similar important scientifi c issues. For many people, the 
reaction is to throw up their hands in hopeless frustration 
and accept that the modern world is impossible to understand and one can only huddle in helpless ignorance at the 
mercy of its mysterious and inexplicable behavior.
 In fact, much of the world around us and the technology of our everyday lives is governed by a few basic 
physics principles, and once these principles are understood, the world and the vast array of technology in our 
lives become understandable and predictable. How does 
your microwave oven heat up food? Why is your radio 
reception bad in some places and not others? And why 
can birds happily land on a high-voltage electrical wire? 
The answers to questions like these are obvious once you 
know the relevant physics. Unfortunately, you are not 
likely to learn that from a standard physics course or 
physics textbook. There is a large body of research showing that, instead of providing this improved understanding of 
everyday life, most introductory physics courses are 
doing quite the opposite. In spite of the best intentions of 
the teachers, most students are “learning” that physics is 
abstract, uninteresting, and unrelated to the world around 
 How Things Work is a dramatic step toward changing 
that by presenting physics in a new way. Instead of starting out with abstract principles that leave the reader with 
the idea that physics is about artifi cial and uninteresting 
ideas, Lou Bloomfi eld starts out talking about real objects 
and devices that we encounter in our everyday lives. He 
then shows how these seemingly magical devices can be 
understood in terms of the basic physics principles that 
govern their behavior. This is much the way that most 
physics was discovered in the fi rst place: people asked 
why the world around them behaved as it did and as a 
result discovered the principles that explained and predicted what they observed.
 I have been using this book in my classes for several 
years, and I continue to be impressed with how Lou can 
take seemingly highly complex devices and strip away 
the complexity to show how at their heart are simple 
physics ideas. Once these ideas are understood, they can 
be used to understand the behavior of many devices we 
encounter in our daily lives, and often even fi x things that 
before had seemed impossibly complex. In the process of 
teaching from this book, I have increased my own understanding of the physics behind much of the world around 
me. In fact, after consulting How Things Work, I have had 
the confi dence to confront both plumbers and airconditioner repairmen to tell them (correctly as it turned out) 
that their diagnosis did not make sense and they needed to 
do something different to solve my plumbing and AC 
problems. Now I am regularly amused at the misconceptions some trained physicists have about some of the 
physics they encounter in their daily lives, such as how a 
microwave oven works and why it can be made out of 
metal walls, but putting aluminum foil in it is bad. It has 
convinced me that we need to take the approach used in 
this book in far more of our science texts.
 Of course, the most important impact is on the students in my classes that use this book. These are typically 
nonscience students majoring in fi elds such as fi lm 
studies, classics, English, business, etc. They often come 
to physics with considerable trepidation. It is inspiring to 
see many of them discover to their surprise that physics is 
very different from what they thought—that physics can 
actually be interesting and useful and makes the world a 
much less mysterious and more understandable place. I 
remember many examples of seeing this in action: the 
student who, after learning how both speakers and TVs 
work, was suddenly able to understand that it was not 
magic that putting his large speaker next to the TV distorted the picture but in fact it was just physics, and now 
he knew just how to fi x it; the young woman scuba diver 
who, after learning about light and color, suddenly interrupted 
class to announce that now she understood why it was 
that you could tell how deep you were by seeing what 
color lobsters appeared; or the students who announced 
that suddenly it made sense that the showers on the fi rst 
fl oor of the dorm worked better than those on the second 
fl oor. In addition, of course everyone is excited to learn 
how a microwave oven works and why there are these 
strange rules as to what you can and cannot put in it.