In electromagnetism, there are 4 rules related to the hand, please explain them in detail

1.Ampere's regularity.

is the relationship between the direction of the DC current and the direction of the magnetic inductance line:

The thumb points in the direction of the current and holds the wire, and the remaining four fingers point in the direction of rotation of the wire.

When circulating current, the four fingers are in the same direction as the current, and the direction of the thumb is the direction of the magnetic line.

2.The right-hand rule.

A rule that determines the direction of the dynamic electromotive force generated in the conductor when the conductor cuts the magnetic inductance line in motion. The right-hand rule reads:

Stretch out your right hand, so that the thumb is perpendicular to the other four fingers and are all in the same plane as the palm, put the right hand into the magnetic field, let the magnetic inductance line perpendicular to the palm of the hand, the thumb points to the direction of the conductor movement, and the other four fingers point to the direction of the dynamic electromotive force. The direction of the generated electromotive force is the same as that of the induced current generated.

3.The left-handed rule.

The relationship between the direction of the ampere force on a wire with a current, the direction of the magnetic inductance line, and the direction of the current

The thumb is perpendicular to the other four fingers and in a plane with the palm, so that the magnetic inductance line enters the palm perpendicular, so that the four fingers point in the direction of the current.

4.In addition, the Lorentz force is also judged by the left-handed rule:

When a charged particle moves in a magnetic field, if the positive point four fingers point in the direction of the particle's motion, if it is negatively charged, it is the opposite.

It can be known that as long as it involves the problem of magnetic inductance lines and forces, use the left hand; When it comes to the question of current and magnetic lines, you use the right hand.

In fact, there are three main ones, and the second of them is used to judge the ampere force and the Lorentz force.

1. Ampere's rule (right-hand spiral rule): used to determine the direction of the magnetic field generated by the current. The details are as follows:

The magnetic field generated by the linear current: the thumb is the direction of the current, and the four fingers are the direction of the magnetic inductance line. Toroidal current and energized solenoid:

The thumb is the n-pole direction of the annular internal magnetic field, and the four fingers are the current direction.

2. The left-hand rule: used to judge the direction of force, as follows: Ampere force:

Stretch out the palm of the left hand, all fingers are coplanar with the palm, the thumb is perpendicular to the four fingers, the magnetic inductance line enters through the palm, the four fingers are the direction of the current, and the thumb is the direction of the ampere force received. Lorentz force: Other, like the ampere force, the four fingers are the direction of the positive charge motion or the opposite direction of the negative charge motion.

3. The right-hand rule: (a special case in Lenz's law) is used to determine the direction of the induced current: the specific method is:

Stretch out the palm of the right hand, all fingers are coplanar with the palm, the thumb is perpendicular to the four fingers, the magnetic inductance line enters through the palm, the thumb is the direction of the conductor cutting the magnetic inductance line, and the direction of the four fingers is the direction of the induced current generated.

The principle of cutting the magnetic inductance line to generate an electric current is:

Matter is composed of positively charged nuclei and negatively charged electrons, when the conductor cuts the magnetic inductance line, the positive and negative charges inside the conductor will be forced, but they are forced in opposite directions, at this time the nucleus occupies a few of the mass of all conductors, and the particles with positive and negative charges conform to the conservation of momentum, so the phenomenon of the nucleus moving and the electrons moving.

Therefore, in fact, after understanding this content, the left hand is the same as the right hand, both of which are moving charges and are stressed in the magnetic field.

Electromagnetic Induction:

If a part of the conductor in a closed circuit moves in a magnetic field to cut magnetic inductance lines, the electrons in the conductor will be subjected to the Lorentz force, which is a non-electrostatic force that can cause a potential difference and generate an electric current.

The direction of the induced current can be right-handed rule, and the word "force" can be found to be left-handed, so use the left hand; And the word "electricity" is right-handed, so use the right hand to memorize the mantra: left to force right electricity judgment, which was first discovered by Faraday.

The right-hand rule is used in electromagnetism, and the right-hand rule is mainly used to determine the direction of the force independent of such as or. If it's about force, it's all about the left-handed rule. That is, the left hand is used for the force, and the right hand is used for the rest (the dust is generally used to judge the direction of the induced current).

A general term for the electrical and magnetic properties expressed by the Zen quality of the oak. Such as electromagnetic induction, electromagnetic waves and so on. Electromagnetism was discovered by the Danish scientist Oster. The cause of electromagnetic phenomena is that the movement of electric charges produces fluctuations and forms a magnetic field, so all electromagnetic phenomena are inseparable from electric fields.

Physical application. A rule that determines the direction of the induced current in a wire moving in an external magnetic field, also known as the motor rule. It is also the law for judging the relationship between the direction of the induced current, the direction of the conductor movement, and the direction of the magnetic field lines.

The flat hand shape is suitable for the generator palm is the direction of the magnetic field, the thumb is the direction of the object movement, and the finger is the direction of the current, to determine the direction of the dynamic electromotive force generated in the conductor when the conductor cuts the magnetic inductance line.

Left-handed rule (Ampere's rule): Knowing the direction of the current and the direction of the magnetic inductance line, the direction of the force on the energized conductor in the magnetic field, such as an electric motor.

Stretch out your left hand, let the magnetic line pass through the palm of your hand (palm aligned with the n pole, the back of the hand with the S pole), and the four fingers point to the direction of the current, then the direction of the thumb is the direction of the conductor force.

The principle is: when you draw the magnetic inductance lines of the magnet and the magnetic inductance lines of the current, the two magnetic inductance lines are intertwined, and according to the vector addition, where the magnetic inductance lines of the magnet and the current are in the same direction, the magnetic inductance lines become dense; In the opposite direction, the magnetic lines become sparse. One of the characteristics of magnetic inductance lines is that each magnetic inductance line repels each other!

The pressure is high in places where magnetic inductance lines are dense, and the pressure is low in places where magnetic inductance lines are sparse. So the pressure on both sides of the current is different, and the current is pressed to one side. The direction of the thumb is the direction of this pressure.

Right-Hand Rule: A rule that determines the direction of the induced current generated in the conductor when the conductor cuts the magnetic inductance line motion. (Generators).

The content of the right hand rule is: stretch out the right hand, so that the thumb is perpendicular to the other four fingers and are in the same plane as the palm, put the right hand into the magnetic field, let the magnetic inductance line perpendicular to the palm of the hand, the thumb points to the direction of the conductor movement, and the other four fingers point to the direction of the induced current.

It's not a matter of memory. The content of the left-hand rule and the right-hand rule must be very clear to the students. The problem I encountered with a classmate was mainly that he didn't know whether to use the left-handed rule or the right-hand rule after getting a specific problem.

This is a key. The key to the problem is to ask students to figure out what the physical phenomenon is when the left-hand rule is applied and what kind of physical phenomenon the right-hand rule applies. The left-handed rule says that the magnetic field exerts force on an electric current, or the force exerted by a magnetic field on a moving charge.

In this case, you should use the left-handed rule, which is the key. After the judgment is made, it is time to use the left-handed rule, and the judgment is made according to the relationship between the three directions mentioned by the left-handed rule, and the problem will not be too big. The right-hand rule is the direction of movement of the induced current generated by the wire when the wire is cut in the magnetic field and the magnetic inductance line moves.

The direction of the magnetic field, the movement of the cutting magnetic inductance line, and the direction of the electromotive force are the way in which the current is induced.

The left-hand rule (electric and magnetically generated force) is to determine the direction of the ampere force experienced by the energized wire in the magnetic field, the direction of the four fingers pointing to the current, and the direction of the thumb pointing is the direction of the ampere force of the energized wire in the magnetic field (or to judge the direction of the Lorentz force experienced by the charged particles when moving in the magnetic field, the four fingers point to the direction of the positive charge motion or the negative charge motion is in the opposite direction, and the direction pointed by the thumb is the direction of the Lorentz force of the energized wire in the magnetic field).

The right-hand rule is to judge the direction of the induced current (magnetic electricity) when the wire cuts the magnetic inductance line, the thumb points to the direction of the wire movement, and the direction pointed by the four fingers is the direction of the induced current.

The right-hand rule is generally rarely used, and is basically used when the problem of electromagnetic induction involves the generation of electromotive force; The left-handed point is used in a wide range of fields, and is widely used in electromagnetism to determine the ampere force direction of energized wires and the Lorentz force direction of dotted particles.

Summary. Right hand. Because the left-handed rule:

It is used to determine when an energized conductor is subjected to a magnetic field force in a magnetic field. The right-hand rule: It is used to determine the direction of the induced current (or electromotive force) generated by the movement of the conductor cutting the magnetic inductance line.

Right-hand spiral rule: It is used to determine the direction of the magnetic field (the direction of the magnetic inductance line) generated by the electric current.

The induced current generated by the magnet enters another conductor that is in the magnetic field, whether it is the left-handed rule or the right-hand rule.

Right hand. Because the left-handed rule: it is used to determine that an energized conductor is subjected to a magnetic field force in a magnetic field draft.

The right-hand rule: It is used to determine the direction of the induced current (or electromotive force) generated by the movement of the conductor cutting the magnetic inductance line. Right-hand spiral rule:

It is used to determine the direction of the magnetic field (the direction of the magnetic inductance line) generated by the electric current.

The question is how the coil on one side of a closed loop is moved by the right-hand rule or the left-handed rule when the induced current generated on one side of the rough posture is on the other side of the other side?

Right hand. At this time, the coil on the right does not rotate, but there is an electric current and a magnetic field, so why not use the left-hand rule to determine the direction of its movement?

It is clear whether there is electricity or an existing magnetic field induction.