Without a doubt, all of a child likes to play with a magnet.Get hold of a permanent magnet was very simple: it needs to find an old column, remove it from the speaker, reproducing, after simple "vandalnyh action" to get her out of the ring magnet.Not surprisingly, many experiments were carried out with metal shavings and a piece of paper.Sawdust placed stripes - along the lines of the field strength.
in electrical engineering much more widespread than permanent and electromagnets.Of course in physics it is known that when an electric current flows through a wire around the last a magnetic field, the magnitude of which is directly related to the current value of the current.
Doubters may repeat the simple experiment of Oersted, when close to a straight conductor with a current placed compass.The arrow will deviate from the geographic north pole of the planet (perpendicular to the wire).The direction of the deviation can be determined using the right hand rule: place your right hand palm down parallel conductor.4 fingers should point in the direction of the current.Then bent 90 degrees the thumb indicates the direction of the deviation of the arrow.Around the straight wire magnetic field has the form of a cylinder with a wire in the middle.But the line of tension to form a ring.In electrical
these magnetic fields are used primarily in the coils.You can often hear the expression "the magnetic field of the solenoid."Imagine an ordinary nail and thin wire insulation.Gradually winding wire on a nail, we get a solenoid.In this case, the nail affects the magnetic field of the solenoid, but this is a topic for another article entirely.It is important to understand exactly what is meant by the term.Now, if the coil connected to a current source, then around the magnetic field will arise.
energy of the magnetic field of the solenoid is directly proportional to the square of the value of the inductance and the current passing through the coils.In turn, the inductance depends on the square of the number of turns.Observe the winding structure: this can be a simple case of a single layer of turns, as well as a multilayer structure where the current direction in the turns of the corrective action provides for the total energy.The solenoids are used in the circuits of trams, macerator, contactors, and so forth.
magnetic field of the solenoid is a ring that go from one end of the winding and the members of the other.Inside the coil lines of force are uninterrupted and extend in a dielectric medium or the conductive core.Impact: The polar field of the solenoid.The lines out of the magnetic north pole, and returned to the South.It is not hard to guess that the magnetic field of a solenoid depends on the polarity of the current source connected to the ends of the wire.The magnetic properties of the solenoid substantially coincide with the permanent magnet.This allows the use of a solenoid as the solenoid.In production, you can see the cranes that have a hook instead of a disc magnet is placed.This is the "big brother" of the solenoid - winding on the core.The peculiarity of electromagnets is that the magnetic properties exist only when current flows in the coils.
addition solenoids are often used toroids.These are the same turns of wire wound on the magnetic core but a circular shape.Accordingly, the magnetic field of the coil and toroid different.The main feature is that the lines of force of the magnetic fields extend in the warp-magnetic circuit inside the coil, rather than outside, as in the case of the solenoid.All this indicates a high efficiency coil on an annular magnetically conductive material.Impact: The toroidal transformers are reliable and have lower losses than their usual counterparts.
