Science Buddies: "Ask an Expert"

My son is doing a project on electricity and wants to know how it generates movement. Can someone please tell me what I need in order to build an electricity generator that can show how it generates movement?

Avictor - I may be misunderstanding your question a little, but I think it relates to the conversion of electricity to mechanical work, or movement. The most common process involves electromagnetism, and the most common vehicle is the electric motor. Magnetic forces acting between the rotating part of the motor, the rotor, react with a magnetic field of the stationary part of the motor, the stator. You can look up many references about AC or DC motors and better understand motor theory and operation, some within the project suggestions in the Science Buddies project home. The most common method of generating electricity is nearly the reverse of this hardware, where mechanical effort to turn the rotor of a generator or alternator within the stator produces electricity. While there are other methods to produce movement using electricity (electrostatics, piezo effect and others). This process of electrical conversion is by far the most common. Often I would evaluate the mechanical and electrical efficiencies of small permanent magnet electric motors by simply connecting identical motors to each other. Turning one motor shaft would produce rotation in the other motor shaft. In essence, mechanical energy converted to electrical energy, back to mechanical energy. A lot of losses were involved, but it was an interesting phenomena. Don't know if this answers your question, you might take this brief info, do some other research and come back to the Experts with a follow-on.

Rick Marz

Avictor,
The Science Buddies Project Ideas page has a simple electric motor project that demonstrates the concept Rick outlines. It's fairly easy and even has a kit available, although you could probably find everything you need at your local electronics store for cheep. The project can be found @

https://www.sciencebuddies.org/science- ... p051.shtml

As mentioned, there are many ways electricity can be converted into mechanical work, but this project will demonstrate a very common way, in an easy to manipulate and test configuration.

The following site may also help you and your son with initial research: http://en.wikipedia.org/wiki/Electric_motor

Good luck. Hope this helps,
theborg