In this Instructable, I show how to make a special 2-piece homopolar motor with a bass speaker, some coins, a battery and two pieces of copper wire.
A neodymium magnet can be used instead of the bass speaker and coins.
This is a great display for Valentines Day...or any day of the year!
The homopolar motor is the simplest form of electric motor. It consists of a battery, a conductor, and a magnetic field.
Unlike other electric motors, the homopolar design doesn't require changing magnetic fields to work. It is a demonstration of the Lorentz Force.
For detailed info, see Wikipedia under "Homopolar Motor" and "Homopolar Generator".
The flat Heart shape is the most basic of homopolar motors. The Heart with legs is the next most simple shape. With a little ingenuity, the two shapes can be combined into one spinning body!
The above movie shows a bass speaker as the source of the magnetic field for the Heart homopolar motor. Pennies are used as a commutator.
Note: No neodymium magnet is needed in this case!
Song is "Be Excellent To Each Other", courtesy EJ Gold, from the album "California Dreams" .
The above movie shows a traditional neodymium magnet used as the magnetic field for the Heart motors.
Background music is a non-traditional band called Wolf Parade from Montreal, with "This Heart's On Fire". (Used with band permission)
Note: Unfortunately, mere permission from the band was adequate for Warner Music, and the music of this video has been stripped from it by them.
Here is a YouTube video with the "This Heart's On Fire" song, so that you can try playing it at the same time as the above movie...http://www.youtube.com/watch?v=0Xq4o-kE-j8
Step 1: Materials and Tools
- 3 foot (1 metre) of AWG 10 gage (preferred), or up to 18 gage, solid copper wire.
- AA battery (I recommend the Duracell AA NiMHrechargeable battery with 2650 MAh rating)
- 10 inch or better bass speaker (or use a good sized neodymium magnet)
- 7 Canadian magnetic pennies, or other coins as a commutator
- (optional) Neodymium magnet 1/2 inch x 1 inch minimum (such as # DX08 from K&J Magnetics )
- Soldering iron
- Wire stripper
- D cell size battery or tube of same size (for forming wire)
- nail or centre-punch