Brushed DC Motor
Build a spinning motor with a real commutator from a coil, magnets and a battery.
Start building ↓The build
Wind the rotor
Wind a flat coil and leave two straight leads as the axle.
Make the commutator
Sand insulation off only one side of each lead.
Build supports
Bend paper clips into cradles wired to the battery.
Spin it up
Place magnets nearby and give the coil a flick to start.
The half-stripped leads switch the coil's current on and off each half-turn, so the magnetic push always drives rotation the same way.
A closer look
This switching (commutation) keeps torque pointing the right direction; remove it and the coil would just oscillate and stop.
Variables to test
- 1 Strip both sides fully — why won't it spin?
- 2 Add a second magnet. Does torque increase?
More Physics
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Coil insulated wire around an iron bolt and a battery turns it into a magnet you can switch on, off, and strengthen at will.
Pendulum Timer
A swinging mass keeps remarkably steady time — build one and discover what really sets its rhythm.