Lorentz Force - Homopolar Motor (nail)
At Christmas 1821, Michael Faraday, British chemist and physicist invented the origin of very interesting and also very simple DC rotary engine, called homopolar.
This experiment demonstrates variant with nail.
Educational phase: motivation
- ferrite or neodymium spherical magnet
- copper wire
- battery type AA
Put the magnetic ball on the head of the nail a that with the other side od the bottom battery contact. Thanks to magnetic force do not drop. At the upper contact of the battery pull the endof the wire.
The other end of the wire attach to the bullet.
The sphere with nail begins to rotate.
Principle homopolárního bike is based on the magnetic field on the conductor with the flow. It uses the fact that coated neodymium magnet can pass an electrical current. The magnet is thus fulfills two functions - it creates a magnetic field while electrically connecting one pole to the other batteries. The result is a rotation of the magnet and screw. The direction of rotation of the magnet wires or specify using good old Fleming's left hand rule, you know the hours of physics:
"Put left hand on the wire so that the induction line B enter into the outstretched palm and fingers pointing direction of the current I Bias thumb indicates the direction of the applied force F".