Electromagnets come in all sizes, from little ones that make doorbells ring, to enormous magnets that pick up entire cars. There are many uses for electromagnets; cassette players, VCRs, stereo speakers, and televisions are a few of the uses for smaller electromagnets.
Now that you have built an electromagnet, explore Using Electromagnets to find out more about how electromagnets are used. Note how electromagnets work in each of these devices:
speaker
electric bell
relay
electric motor
In several paragraphs, summarize some of the uses of electromagnets described in Using Electromagnets. Explain the function of the electromagnet in the devices described. Also, discuss how the electromagnets in these devices are like the one that you built.
Very large electromagnets also are being used in Germany and Japan to lift and drive trains called maglev trains. Maglev trains have no wheels. Instead, they use magnets to run above special rails. The magnets actually lift the train above the rails. Because the train is not actually touching the rails, there is no friction. With no friction, the train runs smoothly and very fast, up to 500 km/h (300 mph).
