What is an electromagnet?
Electromagnets are temporary magnets made from electricity that have a functioning magnetic field only when current passes through them. Many objects around you contain electromagnets. They are found in electric motors loudspeakers, generators, microphones, and cranes. Very large and powerful electromagnets are used as lifting magnets in scrap yards to pick up, then drop, old cars and other scrap iron and steel.
Make your own electromagnet!
- Long nail (or screwdriver, that is mostly a nail with a specific tip and a handle). Iron works best, but steel will work also.
- Roughly 1 meter (about 3 feet) of thin copper wire.
- A 6-volt or 9-volt battery.
- Any kind of steel material except galvanized.
- Wrap the wire around the screwdriver leaving a length on each end for connecting to the battery.
- Hook the wire to the battery by looping the ends of the length to each battery post.
- Tip: use a cloth to hold the battery as it will get hot after a few minutes.
- Holding the battery, bring the copper coiled nail close to the metal and observe how the screwdriver now acts as a magnet to attract the paper clip.
- To be safe and to save your battery, promptly disconnect the wire from the battery when you’ve finished the demonstration.
Using electromagnets to make things hover
Electromagnets are used in hover technology, making things appear to be floating in mid air! Maglev trains work using electromagnets to hover the train above the tracks and change the polarity of the electromagnets in the tracks to help the train move forward.
Maglev trains do not have an engine — at least not the kind of engine used to pull typical train cars along steel tracks. The engine for maglev trains is very different to your usual mechanical engine. Instead of using fossil fuels, the magnetic field created by the electrified coils in the guideway walls and the track combine to propel the train, making the maglev hover.
The Maglev Train