We take motors and generators for granted because they are so successful and reliable. Thank magnetic fields. Magnetic fields have completely changed and improved our way of life, compared to just 200 years ago. We have electric motors everywhere, in refrigerators, fans, elevators, cars, computers, and toys.
This book shows that magnet and motor experiments have real uses and applications. It should not be hard for the reader to realize how important motors and generators are to modern life styles (starting your car, playing DVDs, electric tools, dishwashers, air conditioners, elevators, household water pressure).
Electric motors are possible because magnetic fields create mechanical forces, like a vacuum cleaner sucking up dirt or a kid spinning a spinning wheel at a playground. Magnetic fields are created from electric current, which allows motors and mechanical spinning. Electric motors move half the things around us, like tools, refrigerator pumps, and Blu-ray disks. The other half, mostly for cars, is the combustion engine.
Generators are also possible using magnetic fields. Generators are very similar to electric motors, just in reverse, and supply most of the electricity you use every day.
Generators work because moving wires through magnetic fields go the other way and create electric current. By steam power or water power, we spin turbines and generators to create electricity that powers our cities and lives, such as light bulbs, computers, and dishwashers.
Two audiences were in mind when writing this book. One is a young person who is interested in how things work, probably with the help of a parent. Another is two college students, probably history or business majors, discussing how things work over a beer. These two business majors will probably be the boss of the engineer young person when they all grow up.
