Home CRAFTS Science Experiment DIY Button Battery Homopolar Motor

Science Experiment DIY Button Battery Homopolar Motor

A homopolar motor is a direct current electric motor with two magnetic poles, the conductors of which always cut unidirectional lines of magnetic flux by rotating a conductor around a fixed axis so that the conductor is at right angles to a static magnetic field.

source/image: DaveHax

How to make a Homopolar motor from a battery, magnets and copper wire. Fun science experiment.I make different designs and use different sized batteries including a tiny button battery. Watch the video from DaveHax for more info:

The homopolar motor is driven by the Lorentz force. A conductor with a current flowing through it when placed in a magnetic field which is perpendicular to the current feels a force in the direction perpendicular to both the magnetic field and the current.

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Because the axis of rotation is parallel to the magnetic field, and the opposing magnetic fields do not change polarity, no commutation is required for the conductor to keep turning.Materials needed: Copper wire, Double A battery, 1 half inch diameter cylindrical neodymium magnet, Needle nosed pliers, and a wire cutter.