Hand-Crank Generator
Spin a magnet past a coil and you generate real electricity — enough to light an LED by hand.
Start building ↓The build
Wind the coil
Wind hundreds of turns of wire onto the bobbin.
Mount the magnet
Fix magnets on a shaft that spins close to the coil.
Wire the LED
Connect the coil ends to an LED.
Crank it
Spin fast and the LED glows.
A moving magnet changes the magnetic flux through the coil, which induces a voltage that drives current — electromagnetic induction.
A closer look
Faraday's law says induced voltage rises with more turns, stronger magnets, and faster spinning, which is exactly how power-station generators work.
Variables to test
- 1 Add more coil turns — does the LED brighten?
- 2 Spin faster and slower; relate speed to brightness.
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