||The English used in this article may not be easy for everybody to understand. (September 2011)|
|Electricity · Magnetism|
The magnetic field is the area around a magnet in which there is magnetic force. Moving electric charges can make magnetic fields. Magnetic fields can usually be seen by magnetic flux lines. At all times the direction of the magnetic field is shown by the direction of the magnetic flux lines. The strength of a magnet has to do with the spaces between the magnetic flux lines. The closer the flux lines are to each other, the stronger the magnet is. The farther away they are, the weaker. The flux lines can be seen by placing iron filings over a magnet. The iron filings move and arrange into the lines. Magnetic fields give power to other particles that are touching the magnetic field.
In physics, the magnetic field is a field that passes through space and which makes a magnetic force move electric charges and magnetic dipoles. Magnetic fields are around electric currents, magnetic dipoles, and changing electric fields.
When placed in a magnetic field, magnetic dipoles are in one line with their axes to be parallel with the field lines, as can be seen when iron filings are in the presence of a magnet. Magnetic fields also have their own energy and momentum, with an energy density proportional to the square of the field intensity. The magnetic field is measured in the units of teslas (SI units) or gauss (cgs units).
There are some notable specific kinds of the magnetic field. For the physics of magnetic materials, see magnetism and magnet, and more specifically diamagnetism. For magnetic fields made by changing electric fields, see electromagnetism.
The electric field and the magnetic field are components of the electromagnetic field.
Other pages [change]