Electricity and magnetism are closely linked. In this project we created a simple electromagnetic train which would move down a copper coiled track all by itself. To do this experiment , you would need to slide a train ( made up of a battery with strong magnets on each end) inside a track (made up of copper coil).
Click the video below to see it in action.
What you need
The supplies you would need for this project can be easily found in home depot or you can order them at Amazon.
- 18 Gauge Copper wire ( buy online here )
- AAA batteries
- 6 to 8 neodymium magnets ( buy online here )
- Crayola marker
Next, wrap the copper wire tightly around the crayola marker, spooling the wire to make a long slinky. Remove the coil from the marker and stretch it out just enough so that each winding of the coil doesn’t touch the one next to it.
Make two stacks of 3 neodymium magnets each, orient them such that both stacks repel each other. Place the battery in the middle of the two stacks of repelling magnets.
Put the copper slinky on a flat surface and place the battery train into the tube, it should zip down the coil and out the other side !
How does it work
An electric current creates a magnetic field. When the train is placed inside the copper coil, a magnetic field is created by the current flowing from the battery through the magnets and the coil. This magnetic field is similar to the magnetic field of a bar magnet. Now, the neodymium magnets have their own magnetic fields and since they are repelling each other, their magnetic force is pointing in the same direction.
Inside the copper coil, the magnetic field of the magnets push against the magnetic field created inside the coil , making the magnets and battery move and pull the “train” along. And as the train moves, the magnetic field moves with the train and the train get a steady motion.
While doing this experiment, we faced couple of issues so I want to breakdown all the steps you need to make this experiment run smoothly.
- The magnets must be wider than the battery, since they’ll be in contact with the wire to create current.
- The coil should be wide enough so that the train made up of AAA battery and neodymium magnets can slide inside easily and at the same time the magnets and coils are in close proximty. I found a crayola marker is the perfect width to make a copper coil.
- If you wind the track’s coil too far apart, the train will run very slow. But if you space them slightly farther apart, the train will zoom around at a very satisfying speed.
- If the train doesn’t move, try flipping the magnets around.
- Be very careful with these magnets, they break apart very easily and are very strong. If you need to separate the magnets, slide each magnet to the corner and pull it apart. Please keep them away from children as they can be very dangerous if swallowed. It is also said that their magnetic field is so strong that it can cause damage to the phones and electronics around them.
- If the train starts running slow after a few try, replace the old battery with a brand new battery as the battery inside the coil creates an electrical circuit and burns it out pretty quick.
If you looking for more science related experiments, check them out here.