Why do energized solenoids produce magnetic fields

Because of electromagnetic induction, energized conductors generate magnetic fields.

Magnetic effect of electric current (kinetic electricity produces magnetism): Oster discovered that any wire that is passed with an electric current can produce a magnetic field around it, which is called the magnetic effect of electric current.

A non-magnetic metal can produce a magnetic field with an electric current that has the same effect as a magnet.

The magnetic field generated around a long straight wire with an electric current passing through it.

A magnetic field is generated around a long straight wire that is current-flowing, and the magnetic field lines are shaped as concentric circles closed with the wire as the center, and the direction of the magnetic field is perpendicular to the direction of the current.

The strength of the magnetic field is 1:

H (Gauss) 2i (Amps) 10R (cm) <; == Long straight wire.

i: The total current on the guide wire, which can be increased by increasing the number of turns of the coil.

r: is the perpendicular distance from the wire.

Note: The Earth's magnetic field is about Gauss.

Magnetic field strength 2:

Solenoid coil: pipe surface radius a, pipe length l, total number of turns of coil n, p point from the end face of x.

a.Hollow: The magnetic field at point x.

b.If the solenoid is filled with ferrous substances, in addition to the magnetic field generated by the original hollow coil, the magnetic field created by the magnetization of these substances must be added, that is, the total magnetic field strength (b) should be.

b＝h＋4πm＝h＋4πxh＝（1＋4πx）h＝μh

X: Permeability M: Magnetization H: Magnetic field of the hollow coil.

From the above equation, it can be seen that the magnetic field strength generated by a solenoid plugged with a magnetic substance is m times that of an air-core coil. Generally, the value of ferromagnetic substances is between hundreds and tens of thousands.

According to Biot-Savar's law, an electric current generates a magnetic field, and the magnitude of the magnetic field is proportional to the magnitude of the current, so when the current increases, the magnetic field also increases. As for Biot-Savall's law, it is derived from experiments, just like Coulomb's law for electricity.

This is because the current has a magnetic effect, and the magnetic force will increase as the current increases, and it is also related to the number of turns of the solenoid, and the more turns there are, the greater the magnetic force.

Electromagnetic induction. But. These are 2 experiments. When the current becomes larger (or smaller), it is the point of magnetic generation, that is, electromagnetic induction. When the magnetic field becomes larger (or smaller), it is the magnetic effect of the electric current.

This is called the magnetic effect of electric current, which was discovered by the Danish physicist Oster in 1820.

This is the electromagnetic induction that the Danish guy discovered.

It's electromagnetic induction, and besides, you're discovering this phenomenon a little late now.

The direction of the magnetic field inside the energized solenoid is directed from the south pole of the solenoid to the north pole. Energized solenoid externalInductance linesIt is emanating from the north pole of the solenoid and returning to the south pole.

An energized solenoid is externally equivalent to a bar magnet. The magnetic field on the outside of an energized solenoid is similar to that of a bar magnet.

The relationship between the direction of the current in the energized solenoid and the polarity at both ends of the solenoid can be determined by Ampere's rule.

Also known as the right-handed spiral rule.

The amperometric rule for straight-line currents also applies to a small section of straight-line currents. The annular current can be regarded as composed of multiple small linear electrostatic dust flows, and the direction of the magnetic inductance intensity on the central axis of the annular current is determined by the ampere rule of the linear current for each small linear current. Stacked to obtain the direction of the magnetic inductance line on the central axis of the annular current.

The ampere rule of the linear current is basic, the ampere rule of the annular current can be derived from the ampere rule of the linear current, and the ampere rule of the linear current is also applicable to the magnetic field generated by the linear movement of the charge, where the current direction is the same as the positive charge.

The direction of motion is the same, opposite to that of a negative charge.

The judgment of the direction of the magnetic field of the toroidal current is as follows: the right hand is bent, the tips of the four fingers point to the direction of the current, and the thumb and ruler point to the direction of the magnetic field in the coil.

Energized straight wire: Hold the energized straight wire with your right hand so that the direction of the straight thumb is the same as the direction of the current, then the direction of the curved four fingers is the direction around the magnetic line. Energized solenoids:

Hold the energized solenoid with your right hand, the direction of the circle of the four fingers is the same as the direction of the current, and the direction of the thumb is the direction of the internal magnetic inductance line and the direction of the n-pole (North Pole) of the energized solenoid.

Ampere's rule

The amperometric rule for straight-line currents also applies to a small section of straight-line currents. The annular current can be regarded as composed of multiple small linear currents, and the direction of the magnetic inductance intensity on the central axis of the annular current is determined by the ampere rule of the linear current for each small linear current. Stacked to obtain the direction of the magnetic inductance line on the central axis of the annular current.

The ampere rule of the linear current is fundamental, the ampere rule of the annular current can be derived from the ampere rule of the linear current, and the ampere rule of the linear current is also applicable to the magnetic field generated by the linear motion of the charge, where the direction of the current is the same as that of the positive charge and the opposite direction of the movement of the negative charge.

The above content reference:Encyclopedia – Ampere's Rule

This is the magnetic effect of electric current. That is, if a straight metal wire passes an electric current, then a circular magnetic field will be created in the space around the wire. The greater the current flowing through the wire, the stronger the magnetic field generated. The magnetic field is circular and surrounds the wire.

The principle can be explained as Ampere's molecular current hypothesis: Ampere believes that inside the particles of atoms, molecules and other substances, there is a kind of annular current - molecular current, which makes each particle a tiny magnet, and the two sides of the molecule are equivalent to two magnetic poles, but in fact, the electrons in the molecule do not revolve around the nucleus but the electron cloud formed by the probability of electrons appearing in space.

A single-layer winding is a winding in which only one effective side of the coil is embedded in each stator slot, so its total number of coils is only half of the total number of slots of the motor. The advantage of single-layer winding is that the number of winding coils is small, and the process is relatively simple; There is no interlayer insulation, so the utilization rate of the groove is improved; The single-layer structure does not suffer from phase-to-phase breakdown failures.

The magnetic field around the energized solenoid is because when an electric current flows inside the solenoid, a magnetic field is generated, and this magnetic field forms a circular magnetic field area around the solenoid.

This is described by the law of ampere's circulation. Ampere's circulation law refers to the fact that the direction of the magnetic field formed by the current passing through a conductor is perpendicular to the direction of the conductor and the current, and the strength of the magnetic field generated by the current is proportional to the current intensity, so when the solenoid is energized, a magnetic field will be formed around the solenoid due to the presence of current inside the wire, and the strength of this magnetic field depends on factors such as the current strength and the number of coils of the wire.

Typically,The wires inside the solenoid are wound around a magnetic material (e.g. iron core), which increases the strength and stability of the magnetic field, and as a result, the magnetic field around the solenoid becomes more pronounced. This is also the reason why solenoids can exert an attractive or repulsive force on the surrounding magnetic material when energized.

The external magnetic field of an energized solenoid is similar to that of a bar magnet.

The energized solenoid is composed of an energized coil, and its external magnetic inductance lines are emitted from the north pole of the solenoid and return to the south pole, and the bar magnet is around the magnet The magnetic inductance lines are from the north pole of the magnet and back to the south pole, that is, the external magnetic field of the energized solenoid is similar to the magnetic field of a bar magnet.

Summary. In the energized conductor in the perpendicular magnetic field, the directionally moving charge must be affected by the Luo Lun magnetic force, which causes the charge to produce an uneven distribution of the charge in the vertical direction of the current and the voltage generated is the Hall voltage, and this effect is called the Hall effect. Therefore, the Hall effect can be used to measure the strength of the magnetic field.

By measuring the energized solenoid, it can be found that the magnetic field strength is higher when it is close to the nozzle, and the magnetic field strength is smaller when it is far away from the nozzle. And the location is different, and the direction is also different.

The magnetic field strength in the tube is the greatest and the direction is consistent and uniform. The circuit formed by the direction lines of the entire magnetic field resembles an infinite number of elliptical rings passing through the middle of a tube.

Characteristics of the magnetic field distribution of energized solenoids.

It is similar to a bar magnetic field facet. The direction of the magnetic field can change with the direction of the current. The magnetic field is strongest at the poles. The weakest in the middle.

In the energized conductor in the perpendicular magnetic field, the directionally moving charge must be affected by the Luo Lun magnetic force, which causes the charge to produce an uneven distribution of the charge in the vertical direction of the current and the voltage generated is the Hall voltage, and this effect is called the Hall effect. Therefore, the Hall effect can be used to measure the strength of the magnetic field. By measuring energized solenoids, it will be found that:

Close to the nozzle, the magnetic field strength is large, away from the nozzle, the magnetic field strength is small. And the location is different, and the direction is also different. The magnetic field strength in the tube is the greatest and the direction is consistent and uniform.

The circuit formed by the direction lines of the entire magnetic field resembles an infinite number of elliptical rings passing through the middle of a tube.