Discover the power of electromagnetism through this fun experiment! Kids and teens interested in STEAM will love creating their own electromagnetic train while learning about the relationship between electricity and magnetism.
- 20 gauge bare copper wire (must be bare, no coating)
- AAA battery
- 48-inch dowel
- 6 neodymium magnets, 0.5 in. diameter x 0.125 in. thick (regular refrigerator magnets will not work)
- Cut a piece of tape to have it ready.
- Start to unwind the wire.
- Tape one end of the wire securely to the end of the dowel.
- Tightly wrap the wire around the entire length of the dowel.
- Carefully remove the dowel from the coiled wire.
- Make two stacks of three neodymium magnets. Make sure the magnet stacks repel each other. Place each stack of magnets on opposite ends of the battery.
- Slide the battery with the magnets attached inside the coil. It should zip from one end of the copper coil straight through the other side!
- If the train does not move, try flipping the train around. If that doesn’t work, try flipping one of the stacks of magnets around.
- Create a continuous train by forming a circle with the coil. The train will zip around the coil continuously for the battery’s life.
How the Electromagnetic Train Works
When the battery is placed inside the coil and the magnets on either side of the battery are touching the copper coil, a closed circuit is created with electricity flowing to the positive end of the battery through the magnets to the copper wire and back to the negative end of the battery. The copper wire acts as a conductor for the circuit. The electricity flowing through the copper wire creates a magnetic field. The magnetic field is strongest in the center of the battery at first, but then it spreads out and becomes weaker at the end, creating a non-uniform magnetic field. This causes the magnets in front to feel a stronger push in one direction while the magnets in the back feel pulled, causing the battery to move through the coil.
Interested in Learning More About Electromagnetism?
The Summer Institute for the Gifted (SIG) offers exciting courses in STEAM plus humanities and fitness for gifted and talented students ages 5-17, including the course Electricity + Magnetism: A Powerful Pair!