Electromagnet Principle

Circular coil leading to the magnetic field of current formation

1. The magnetic field direction at the center of the coil allows a small section of wire on the coil to be considered as a straight line. 2. Phone: Next section to be introduced. 3. Ammeters, voltmeters, galvanometers, and so on. 4. Electric bells, etc. < An electromagnet is an electrically charged spiral coil with an iron core inside. When an iron core is inserted into the spiral coil, it is determined by the right-hand rule of Ampere.

On a circular coil with current, each small segment of the current generates a magnetic field that points in the same direction within the coil, hence the magnetic field inside the coil is stronger than that produced by a straight wire carrying the same current.

When three circular wires are carrying current, the magnetic field outside the coil is weaker due to the inconsistent directions of the magnetic fields generated by each small segment of current.

The larger the current in a 4 circular loops, the smaller the radius, the greater the magnetic field strength at the center of the loop, as offered by Linqu XingSheng Magnetoelectric.

The magnetic line shapes of five circular loops and disc-shaped thin magnets are similar.

2. Magnetic Field of Spiral Coiled Current

A long helical coil formed by wrapping a long wire is equivalent to a series of circular coils. Each circular wire creates a magnetic field at its center that is in the same direction, enhancing the effect. Therefore, the magnetic field at the center of the coil is stronger than that of a single circular coil.

The magnetic lines within the 2-coil form straight lines with the same direction, while the magnetic lines at approximately the ends of the coil gradually curve outward.

The magnetic line characteristics of a helical coil are similar to those of a bar magnet, with the magnetic lines inside the coil opposite in direction to those outside.

The intensity of the magnetic field within a 4-coil is directly proportional to the current in the coil and the number of turns per unit length. The direction of the magnetic field within a helical coil is determined by the right-hand rule (Ampere's theorem): grip the coil with your right hand, with your fingers pointing in the direction of the current, and your thumb will indicate the direction of the magnetic field lines within the coil.