Electromagnetic Train
A battery wrapped in magnets shoots through a bare-copper coil tunnel like a tiny maglev train.
Start building ↓The build
Wind the track
Coil copper wire tightly around a pencil to make a long, even tube.
Build the train
Stick two magnets on each end of the AAA battery.
Insert it
Drop the magnet-battery into the coil tunnel.
Launch
The train accelerates through the coil on its own.
The battery drives current through the coil between the magnets, creating a magnetic field that pushes the magnets — and the whole train — forward.
A closer look
Each magnet's contact feeds current into a few loops of coil; that current's field repels one magnet and attracts the other, producing continuous thrust.
Variables to test
- 1 Reverse the magnets on one end — does it stall?
- 2 Wind a tighter coil. Does the train go faster?
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