The principle of operation of the electric motor, first of all, is based on the main laws of electrodynamics, namely, magnetic laws on action of magnetic field on charged particles.
It is required to you
- the textbook in physics, the sheet of paper, a pencil
Instruction
1. Remember school material about the basic magnetic laws. Open the textbook in physics of the 9th class and look at the drawings representing magnetic field of permanent magnets. It is known that magnetic field is generated by charge carriers when they move. The principle of operation of the electric motor is also based on it, actually. It is known that when entering into magnetic field of the conductor with current the last begins to deviate so as if magnetic field pushes out the conductor from itself in a certain party. When current on the conductor does not flow, the field does not perceive it. Force operating on the conductor with current is called Lorentz force. Action of this force is based on action of magnetic field on moving charged particles in the conductor which form by themselves electric current.
2. Take the sheet of paper and a pencil and draw two rectangles carried on some distance from each other. On one rectangle write letter "C", and on another "Ю". Two rectangles will represent two permanent magnets used in electric motors of a direct current. Draw the magnetic lines reaching from the North Pole of a magnet for southern (the direction of lines can be designated by arrows). Present now that the conductor with current perpendicular to lines of magnetic induction is brought in this field. The Lorentz force operating on charges in the conductor will push out this conductor from magnetic field. The direction of action of this force depends on the direction of current in the conductor. And, if to change the direction of current to opposite, then the Lorentz force direction will also change on opposite.
3. Present that you bring in this magnetic field two conductors with currents of opposite directions. Then some of conductors another will be pushed out in one party, and – in opposite. If to get such two conductors on forming there is nobody a cylinder, located opposite each other in relation to an axis of symmetry of a cylinder and to place this cylinder in magnetic field, then action of magnetic field will be expressed that the cylinder will turn on a corner of 90 degrees. If to arrange such conductors on a cylinder more often and to change periodically the direction of current in conductors, then turns of a cylinder will be made on smaller corners and will become more smooth. Thus the electric motor is also implemented.